FI82073B - FRAMSTAELLNINGSFOERFARANDE FOER EPIDERMIN, EN ANTIBIOTISK POLYPEPTID. - Google Patents

Description

1 82073

Method for preparing an antibiotic polypeptide, epidermin -Framställningsförfarande för epidermin, en antibiotisk polypept-peptid

The present invention relates to a process for the preparation of an antibiotic-active polypeptide, hereinafter referred to as epidermin, by means of a new strain of Staphylococcus epidermldis resistant to this substance.

It is known from EP-A-0 027 710 that a certain strain of Staphylococcus epidermidis, namely Staphylococcus epidermidis NCIB 11536 (deposited with the National Collection of Industrial Bacteria, Aberdeen), forms a small-molecule, antibiotic-active polypeptide with broad-spectrum activity. positive organisms and which lyses bacterial cells.

It is further known that Staphylococcus epidermidis strain MF 205 (SM Taylor et al., Int. J. Mass Spectrom. And lon Physics 48, 161-164, 1983) also produces an oligo-peptide having activity against gram-positive bacteria. . It is not clear from the publication whether this strain is identical to the above-mentioned NCIB strain 11536.

It has now been found that a resistant strain of Staphylococcus epidermidis, deposited on 26 October 1984 in the "Deutsche Sammlung von Mikroorganismen" collection under number DSM 3095 and closely related to the abovementioned strain NCIB 11536, produces a similar, mainly after a modified production and further processing method, an epidermin polypeptide having antibiotic activity against gram-positive organisms, which, compared with the products of Staphylococcus epidermidis NCIB 11536 and MR 205 strains, has e.g. significant differences in amino acid composition: 2 82073

Components of Verla jiu:

Lp; term Staph.epidermidis products _______MF 205 _NCIB 11536

Asn 1 -

Asx - 21

Glx - 31

Pro 1 11

Gly 2 22

Area 2 21

Ile 2 21

Phe 2 21

Lys 2 21

Lan 2 - β-Me-Lan 1 -

Dhb 1 -

Tyr 1 1 S - (2-Aminoviny yn) -D-cysteine 1 X - 1-2 -

Dhb is α, β-dehydroaminobutyric acid, Asx and Glx are Asn / flsp j 'and Gln / Glu.

After total hydrolysis of the epidermin with 6N hydrochloric acid (18 hours at 110 ° C), quantitative amino acid analysis by ion exchange chromatography (standard program Biotronik LC 6000 E-device11a) gave the following α-amino acid composition:

Asp (1.00), Pro (0.95), Gly (2.09), Ala (2.03), Ile (2.03), Tyr (0.30), Phe (2.02) and Lys (2.00) (cf. Figure 1). Addition of thio-glycolic acid increased the tyrosine content of the total hydrolyzate to an almost stoichiometric value of 0.93.

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The protein amino acid configuration was obtained from the total hydrolyzate by gas chromatography of pentafluoropropionyl amino acid n-propyl ester. The separation was performed in a chiral L-valine-tert-butylamide-polysiloxane stationary phase (Chirasi1-Va1). By comparing the test mixture with amino acids of known configuration, the L-form could be found as the configuration of the above components (cf. Figure 2).

In addition to these protein amino acids, the following e i-p ro t. E i in yacic acids are added: pelvic acid (2), β-methyllanthionic acid (1) and α, β-dehydroamino novoic acid (1); lanthionine then has the meso configuration and the 3-methyl n t i oni n i 11 a 2S, 3S, 6R configuration. lipidermin further contains an S- (2-aminovinyl) -D-cysteine moiety.

The new epidermin compound can be characterized by the following information: 1. Nature: colorless powder 2. Solubility: very soluble in water / glacial acetic acid:. · Or methanol / glacial acetic acid mixtures, soluble in lower alcohols, insoluble in chloroform, acetone, di- • ·; ethyl ether, petroleum ether.

3. Color reaction with acid gel 1: ninhydrin, chlorine / TDM (TDM = 4,4'-bis- (dimethylamino) diphenylmethane), orsine / sulfuric acid, anisaldehyde / sulfuric acid. Non-diffusible detection under UV light at 254 nm and sprayed with water.

4. TLC chromatography: silica gel ready plates 60 F 2 (Merck) were used.

System A: chloroform / methanol / :: 17% ammonia (2/2/1) RF = 0.73

System B: chloroform / methanol / 17% ammonia (70/35/10) RF = 0.30 L ". System C: n-butanol / glacial acetic acid / water (4/1/1) RF = 0.05 4 82073 6. Stability: Stable at pH values of 2-7, at higher pH values the activity decreases sharply.

7. Molecular weight: about 2160. Depending on the isolation method, it can be obtained as a union, for example as chloride, acetate or phosphate.

8. Ultraviolet absorption spectrum: in aqueous solution, long-wave maximum 267 nm (Figure 3).

9. Infrared absorption spectrum: the IR spectrum of the sample in a potassium bromide ditabine counter (Figure 4).

10. Vinomagnetic resonance spectra 1 H-NMR spectrum: Figure 5, 1 H-NMR spectrum: Figure 6

Fragments suitable for epidermin sequencing were obtained by trypsin cleavage. Reaction with trypsin rapidly reduced antibiotic activity. A jelly-like white precipitate was observed macroscopically in trypsin treatment, which could be separated by centrifugation. The supernatant was lyophilized and gel chromatographed on a 5ephadexG ~ 25 gel (Pharmacia dextran gel) in 1% acetic acid. A chemically uniform fraction stained with ninhydrin, chlorine / TDM, and water (hereinafter referred to as P1) proved to be the N-1 terminus of epidermin trypsin treatment (see below).

The highly hydrophobic, gel-like precipitate consisted of several chemical components formed by trypsin cleavage of the C-terminal piece of the total molecule. A chemically uniform product (hereinafter referred to as P2) was obtained by dissolving the precipitate in dimethylformamide and then gel chromatography on Sephadex LH-20 gel (dextran gel prepared from hydroxypropylated 11a Sephadex G-25 gel, Pharmacia) using dimethylformamide as a propellant. P2 can be detected by water, chlorine / TDM and UV light. The ninhydrin reaction of P2 is negative.

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The amino acid of the P1 piece gave the following composition:

Pro (1), Lan (1). β-Me-Lan (1), Gly (1), Ala (2), lie (2), Phe (1), Lys (2). Because isoleucine was determined to be the N-terminal amino acid by dansylation treatment of the total molecule and because the P2 fragment does not contain isoleucine, the P1 fragment must be the N-terminal cleavage product of the total molecule. Based on trypsin treatment, the C-terminal amino acid of the P1 piece must be lysine.

To further elucidate the structure of the P1 fragment, the C-terminal lyamic amino acid was enzymatically removed by carboxypeptidase B (Boehringer Mannheim). The resulting P12 fragment could be isolated in pure form by gel chromatography on a Sephadex G-25 gel (1% acetic acid). P12 consists of the following amino acids: Pro (1), Lan (1), B-Me-Lan (1), Gly (1), Ala (2), Ile (2),

Phe (1), Lys (1).

Sulfur bridges of lanthionine and S-methylanthionine thioether amino acids inhibit Edman sequence analysis. Reaction of * P12 with Raney-Ni W2 catalyst gives a sulfur-free dodecapeptide. meso-Lan is then converted to D- and L-α 1 anine and G-methyllanthionine to D-aminobutyric acid and L-alanine. The dodecapeptide sequence was determined by Edman digestion and FAB spectrometry: Ι1θ1-Αΐ32-Αΐ33-Εγε ^ -Ρ · Ηθ5-Ι J.e6-Ala7-Abu8-pro9-Gly10-Ala1 ^ -Ala ^ 2.

Various studies on the order of refraction of the P12 block revealed the following structure: is-1: * · Ile-Ala-Ala-Lys-Phe-Ile-Ala-Abu-Pro-Gly-Ala-Ala '-S-1 »· 6 82073

The C-terminal P2 fragment obtained by trypsin digestion can be characterized as follows: Asn (1), Lan (1),

Gly (1), Phe (1), T \ j · (1), α-keto butyric acid and S- (2-aminovinyl) -D-cystene.

α-Keto acid is derived from dehydroaminobutyric acid, which in the sequence of the total molecule follows directly the lysine ^ amino acid. Trypsin cleavage releases the amino groups of dehydroaminobutyric acid; since dehydroaminobutyric acid containing free amino groups is unstable, they are recycled e.g. α-keto acids.

α-Ketobutyric acid n-terminates the trypsin block P2 (the ninhydrin reaction of P2 is negative). In addition to the lanthionine, glycine, phenylalanine, tyrosine, and aspartic acid amino acids identified by total hydrolysis and amino acid analysis, the P2 fragment also has a structural component that is destroyed by total hydrolysis.

This can be characterized by its signals in the λ C nuclear resonance spectra (Figure 6) and the P2 fragment (Figure 8) of epidermin.

An indication of the chemical nature of this amino acid is obtained by reacting P2 with a Raney-Ni W2 catalyst,! forming two main products. In both prepa-; the product isolated by rational HPLC, after total hydrolysis, has another D-alanine group in the amino acid chromatogram formed by this reaction.

The structure of this moiety could be elucidated by heterogeneous hydrogenation of the native antibiotic. The four reaction products H1, H2, H3 and H4 were purified by semi-preparative HPLC, total hydrolysed and gas chromatographed in a • chiral stationary phase (Figure 15). A comparison with the chromatogram of Figure 2 showed an additional peak for H1 and H3, which was identified by its mass spectrum.

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782073 was converted to S- (2-aminoethyl) -D-cysteine. This amino acid was present in the epidermin as an acid-labile S- (2-aminovinyl) -D-cysteine moiety.

Both peptides P21 and P22 generated from the C-terminal P2 fragment by Raney nickel W2 catalyst treatment could be characterized as follows by amino acid analysis and Chirasil-Val gas chromatography:

Reaction products_P 21_P 22 _

Amino acid analysis and 2 D-Ala 1 D-Ala

Chirasil-Val-gas- 1 L-Ala meso-Lan chromatography 1 L-Phe lL-Phe 1 L-Tyr 1 L-Tyr 1 L-Asp 1 L-Asp 1 Gly 1 Gly

In addition, ethylamine blocked both products at the C-terminus. In desulfurization by simultaneous hydrogenation, S- (2-aminovinyl) -D-cysteine was decomposed into D-alanine and ethylamine.

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Sequencing of the bridged heptapeptide P21 (partial hydrolysis; 0.1 N-hydrochloric acid, 93 ° C, 16 hours) gave the following structure: H 3 C-C 12 -CO-CO-Gly-D-Ala-L-.Phe.- L-Asn-D-Ala-L-Tyr-L-Ala-NHEt

The site of the meso-1-anion contained in fragment P22 by partial hydrolysis and the enzymatic fragments of fragments P21 and P22 obtained by various chemical studies could only be combined with the following structure of the trypsin-treated P2 fragment e 82073 I-S -

H 2 C-CH 2 -CO-CO-Gly-Ala-Phe-Asn-Al.a-Ty r-Ala-NH-CH

L-S- CH

The formal substitution of P2 N - the terminally blocking 2-ketov / butyric acid with the dehydro-butyrin amino acid in the native antibiotic and the subsequent condensation of pieces of trypsin peptides Pi and P2 led directly to the heterodetetracyclic epidermin peptide antibiotic:

Structure of a ribosomally synthesized heterodecyclic EPIDERMINE docosapeptide antibiotic: s 82073 meso-1 ant ion i i n i ch2 - S -CH2

I I

H-Ile-Ala-NH-CH-CO-Lys-Phe-Ile-NH-CH-CO-- (S) (R) CH3 β-methylanthionine (S) CH - S - CH2 - NH-CH- CO-Pro-G1y-NH-CH-CO-A1a-Lys - (S) (R) Γ - "11 —— ..il I 'CH3 meso-1 ant ionine CH CH2 ------- s- -— CH2 (S) (2)

- NH-C-CO-Gly-HN-CH-CO-Phe-Asn-HN-CH-CO-Tyr-HN-CH-CO-NH-CH

(1) (S) I (r) ||

CH2 - S - CH

S- (2-amine or i) -D-cysteine

The halves of the individual bioether amino acids near the N-terminus are in each case in the D-configuration (corresponding to the (S) -configuration of the R, S, nomenclature).

The invention thus relates to a process for the preparation of a uniform and thus pure product, called epidermin.

.! The producer of Staphylococcus epidermidis DSM 3095 is grown aerobically at 37 ° C on a rich medium consisting of 2-4% meat extract, 1-3% ma 1la nozzle and 0.25-1% calcium carbonate or 0.25-0.5% of calcium hydroxide. (Percentages herein and always refer to weight percentages unless otherwise indicated.) Maximum antibiotic activity is reached after 1Θ to 23 hours.

Antibiotic enrichment studies were performed, for example, with a culture filtrate from a 10 liter fermentor, whereby the effectiveness of the individual steps was examined by a plate diffusion test. The active components could be enriched by extraction with n-butanol of the culture and descaled culture filtrate, however, n-butanol extraction was only successful at the natural final pH of the culture filtrate of 8.0. Further purification could be performed by separating the followers with lipid substances by ether precipitation. To this end, the butanol extract was evaporated, the residue was dissolved in methanol and five times the amount of cold diethyl ether was stirred in. The activity then remained completely precipitated (diagram in Figure 9).

A particularly suitable enrichment method is also the adsorption of the centrifuged: culture filtrate on an acrylic ester-based polymer: Amberlite XAD-8 or a polymer closely related thereto · (Serva). The epidermin is then not attached to the resin by a single adsorption but by the cation exchange effect of free acrylic acid moieties. This is supported by the fact that the active component could only be removed from the resin by elution with methanol / concentrated hydrochloric acid (99: 1). The strongly acidic eluate must be neutralized with ammonia before evaporation in vacuo. Subsequent precipitation from methanol / ether could be omitted after this further treatment by adsorption on Amberlite XAD-8 resin.

Isolation of the epidermin by adsorption can also be performed already during the growth of the microorganism directly in il 82073 culture medium.

Stability and chromatographic studies were performed with lyophilized butanol extract. Incubation of the product with aqueous solutions of different pH values greatly reduced the activity from pH 10, but the antibiotic is still stable in the pH range 2-7.

The thin layer chromatograms of the evaporated butanol extract contained numerous compounds stained with different spray reagents. Alongside these, the bioauto grams performed provided important indications of the nature of the new active ingredient. In acidic and almost all neutral systems, the antibiotic remains strongly at the starting point on silica gel 60 in thin layer chromatography, while chromatography on alkaline propellants gave Rp values between 0.3 and 0.75. The combination of bioautography and thin layer chromatography in time systems correlated with a compound that could be stained with ninhydrin.

As a result of these preliminary experiments, it could be confirmed that the antibiotic in question is a strongly basic peptide, *: which prevented further treatment by flash chromatography on silica gel 60 because it could not be eluted from the column with acidic or neutral systems.

Chromatography of the Amberlite XAD eluate or lipid-depleted butanol extract on Sephadex LH-20 resin with methanol / acetic acid (95: 5) separated a large number of small peptides, amino acids and salts from the antibiotic medium (Figure 9).

Subsequent Craig amplifying countercurrent extracts could benefit from the experience gained with anti-; in the extraction of biot from the culture filtrate. The antibiotic remained at the beginning of the first liquid-liquid extraction with the n-butanol / acetic acid / 0.1 N acetic acid (3: 1: 3) system.

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In another Craig extraction with a neutral 2-butano 1i / 0.05 N ammonium acetate (1: 1) system, an antibiotic was found in the center of the device. Ammonium acetate could again be removed by lyophilization under high vacuum.

After freeze-drying, the epidermin was obtained in all the sheet metal systems used as a uniform powder.

Purification according to the method of European Patent Application 0 027 710 used freeze-thaw extraction, evaporator evaporation, ultrafiltration, ammonium sulphate precipitation, ion exchange chromatography and gel filtration on Sephadex G-50 or G - 2 5 or G - 15 resin or Biogel P2 gel. Purification according to the invention yields a uniform pure product by adsorbing the centrifuged aqueous filtrate onto Amberlite XAD-8 resin, followed by gel chromatography on Sephadex LH-20 gel and then performing Craig's countercurrent extraction twice. The isolation and purification of the method of the above-mentioned European patent application and the method according to the invention are thus completely different.

Compared to the known method according to the above-mentioned patent publication EP-A-0.027.710, the difference is still the choice of a rich nutrient solution. When the known Brain Heart Infusion: (37 g BHI / 1) produced only very low antibiotic yields, very good results were obtained with the nutrient solution according to the invention containing 2-4? Ί li ha extract, 1-3 / ¾ sugar or sugar alcohol such as malt extract. , maltose, galactose, lactose, mannitol, glucose, glycerin and 0.25-1% calcium carbonate or 0.25-0.5% calcium hydroxide. The best yield was obtained with a nutrient solution having the following composition: 3% meat extract, 2% malt extract and 0.37% calcium hydroxide. Of all the * · carbon sources, the best yield was for maltose after malt extract *. Glucose could only be used with other carbon sources i3 82073. The combination of lactose and maltose or galactose and maltose also gave good results. All other conventional hii1i1 ähtei11 had no or only a very low yield. The addition of all 20 amino acids as a nitrogen source at a concentration of 2 g / l in each case gave the same results as the meat extract. Casamidoacid (Difco) is suitable as a nitrogen source only when adding tryptophan (1-2 mM) and vitamins. Suitable vitamins (preferred concentrations): biotin (0.006 mg / l), nicotinic acid (2.3 mg / l), thiamine (1.0 mg / l), pyridoxine .HCl (12.0 mg / l), calcium pantothenate ( 1.2 mg / l).

The fermentation took place by aerating well at temperatures between 34 and 37 ° C. The best yield development is obtained when the pH of the fermentation is 6.0 to 7.0. No yield occurs if carbonates or hydroxides of divalent cations such as calcium carbonate or calcium hydroxide are not present. For example, after the addition of calcium carbonate, the pH characteristically changes, decreasing to an acidic range, whereby no yield occurs.

When the pH is then raised to a weakly alkaline range, production begins. Instead of calcium carbonate, magnesium carbonate can also be used. With calcium hydroxide ': better results were obtained than with calcium carbonate.

With 50 mM calcium hydroxide, the yield could be further slightly improved compared to 25 mM calcium carbonate. When the strain uses carbon sources (sugar), it forms organic acids that are complexed by divalent cations, thereby simultaneously losing the buffering of the substrate.

Figure 10 shows the results for the number of living organisms:. and the development of antibiotic production in mm / strain of Micrococcus luteus ATCC. The substrates according to the invention have been compared with V. the above-mentioned European patent publication Brain 14 82073

Heart Infusion Platform (Difco).

The calibration line is used to obtain the increases in activity given in the successor plate fusion test up to the time of maximum yield.

The activity of the Brain Heart Infusion nutrient solution was taken as 10U%.

a) Brain Heart infusion Agar 100% b) 3% Meat Extract, 2 · ό Malt Extract, 25 mM Calcium Carbonate11i 200% c) 3% Meat Extract, 2% Malt Extract, 50 mM Calcium Hydroxide 320% These results are not absolute yield values. However, the values obtained by comparison by means of a plate diffusion test unequivocally show that by operating according to the invention the yields could be significantly improved compared with the known method.

The strain used to prepare the epidermin is characterized as follows according to Schleifer & Kloos (Int. J.

: Syst. Bact. 2_5, 50-61 (1975): ‘Gram staining: positive

Cell size: Diameter 0.5-0.8 μm

Colony size: about 1 mm in diameter

Appearance of colonies: Smooth, shiny, slightly raised in the middle

Colonies color: greyish - white

Cells in culture: Often single cells or groups of two, rarely - larger flocks

Hemolysis: Deep hemolysis may occur in cultures applied to sea plates

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Anaerobic growth: The stock also grows under anaerobic conditions

Lysozyme sensitivity: Cells are resistant to lysozyme up to 2 mg / ml

Lysostaphin sensitivity: Cells are already sensitive to lysostaphin at a concentration of 20 ug / ml

Epidermin resistance: detectable up to 1 mg / ml

Other resistance: In liquid culture, the strain has clear resistance to streptomycin (up to 1 mg / ml) and spectinomycin (0.5 mg / ml)

Higher NaCl content: The strain still grows well up to 15% by weight of sodium chloride.

Colonies or brushed cultures are very sticky.

Different carbon sources were evaluated by acid formation and other enzyme reactions were determined by the Api - S taph system (Biomerieux, Niirtingen).

The age system is based on a combination of 20 biochemical reactions. These reactions can be attributed to Kloos &

Schleifer's classification (J. Clin. Microbiol. 1, 82-8 (1975)).

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Table I: C source evaluation and other enzyme reactions

Product- Staph, epid. Staph.epid.

C source or enzyme producer _ _ _____ Kloos & Schleifer Api - Staph

Control D-glucose + k.A. + D-fructose + + · + D-mannose (+) (+) +

Maltose +++

Lactose (+) + O-trenalose D-mannitol '

Xylitol D-melibiosis ~ k.A.

Raffinose ~ k.A.

D-xylose -

Sucrose + + + α-methylglucoside. · K.A.

N-acetylglucosamine - k.A. . +

Nitrate reduction + + + ► 'Phosphatase + + +

Acetylmethylcarbinol + k.A. + formation (Voges- "Proskauer reaction)

Arg ini inidehy drolaas i - k.A. +

Urease + k. A. +, + positive reaction negative reaction: (+) a clear positive reaction occurs only later + variable property K.A. does not print on i7 82073

Staphylococcus epidermidis DSM 3095 strain in sieve sloping tubes with a substrate composition of

Peptone 1q g

Disodium hydrogen phosphate 2 g

Meat extract 8 g

Glucose Gi0g (autoclaved separately)

Saline 3 g PH 7.2 was incubated overnight at 37 ° C and then frozen at -20 ° C. For new experimental batches, a new tube was always thawed, as losses of activity were observed when stored longer at 4 ° C.

The preparation of the epidermin antibiotic is described in more detail below:

The fermentation can be performed in suitable shake flasks. A fermentor of 20 U 1 or larger can also be used to produce larger amounts of material.

In the flask experiments, 500 ml E r le nmey e r-p u 11 o j a with a side tube were used. The flasks were filled with 100 ml of nutrient solution and autoclaved for 20 minutes at 121 ° C. A 1? Ί 4-hour-old pre-culture was used as a transplant.

Incubation was performed at 37 ° C on a rotary shaker at 140 rpm.

For 10 liters of fermentation, a fermentor with a useful volume of 10 L (model MF-14 New Brunswick, Scientific Co., New Brunswick, USA) was filled with 9.9 liters of nutrient solution and autoclaved for 30 minutes at 134 ° C. After cooling, 100 ml of a 4-hour-old preculture were inoculated and fermented at 37 ° C, aeration of 0.6 vmm and a plate stirrer speed of 240 rpm. The relatively strong foam formation of 82073 was prevented by repeated addition of sterile polyol.

2 5 liter fermentation was performed in a 25 liter fermentor (type b 25, Braun / Mlsungen with Umwurf mixing system) using 25 L of nutrient solution supplemented with 3 ml of polyol and sterilized in situ for 30 minutes at 121 ° C. 300 ml of a 4-hour-old preculture was used as a biocrit. The fermentation was carried out at 37 ° C, aeration 0.6 vvm and a stirring speed of 1000 rpm.

Figure 11 shows the course of fermentation in a 10 liter nutrient solution containing 30 g of meat extract, 20 g of malt extract and 5 g of calcium carbonate per liter. From the decrease in pH, a strong increase can be observed, which is accompanied by the wear of the spent carbon source and the formation of acid. The antibiotic can be detected in the culture filtrate at the beginning of the preparation. The yield reaches its maximum after 12-18 hours.

To control the course of fermentation, sterile samples were taken at different times of fermentation. The samples were examined as follows: '(a) pH:

Measurement pH laboratory meter11a (Knick pH mV meter) b) Growth course:

Growth could be monitored by an increase in the number of living organisms.

To this end, 0.5 ml of sterile culture was diluted in saline and plated on 0.1 ml plates (medium: peptone 10 g, meat extract 8 g, cooking salt 3 g, disodium hydrogen phosphate a11i 2 q, glucose 10 g per 1 l).

*. Incubated for 18 hours at 37 ° C, followed by single *. colonies were counted.

li 82073 c) Antibiotic concentration: Samples were centrifuged for 2 minutes in an Eppendorf 3200 centrifuge and 20 supernatant was tested in a plate diffusion assay.

In parallel, a calibration curve was determined using known concentrations.

After reaching the maximum yield, the culture medium was centrifuged in a continuous centrifuge (centrifuge: type LA 71b-4, Loher & Söhne, Ruhstorf / Rott) at 1380 rpm. For optimal cell separation, the flow rate had to be kept very low. The active ingredient was enriched by adsorption on Amberlite XAD-8 resin as shown on page 10 according to the following Example 1:

Example 1 80 liters of culture filtrate were passed through about 8 liters of Amberlite XAD-8 resin. No activity could be detected in the flow-through. Activity was also not eluted in the subsequent water wash. It was then washed with 13 liters of methanol. No activity could be detected in the wash water. Elution was performed with methanol / hydrochloric acid 99: 1 to give the following fractions:

Verse 1: 0.8 1 active: Verse 2: 4.5 1 main activity :: Verse 3: 2 1 active

Verse 4: 2 1 no activity

Verse 5: 1 1 no activity

The fractions were tested for epidermin content by thin layer chromatography, after which the active fractions were combined and evaporated to dryness on a rotary evaporator (81.2 g).

! The residue was taken up in methanol / acetic acid (95/5) (400 ml), the insolubles were separated by centrifugation at 2082073 and gel chromatographed in 50 ml portions on Sephadex LH-20 resin (column 100x5 cm, propellant methanol / acetic acid 95: 5). The positive fractions were combined and evaporated (14.8 q).

Craig's amplification extraction used equipment from Labortec (Basel). The first separation was performed on a 50 ml apparatus in a n-butanoyl / acetic acid ester / 0.1 M acetic acid (3/1/3) system. A sample (5 g) dissolved in the lower phase (100 ml) was separated under the following conditions:

Number of steps: 160

Shaking movements / stage: 70

Shaking intensity: 45

Separation time: 20 min.

The crude product obtained for final purification (4.2 g) was dissolved in 2 g portions of 2-butanoyl / 0.05 N ammonium acetate (50 ml) in the lower phase of the system and purified in a 10 ml apparatus with 440 elements.

Number of steps: 440

Ra v i s t e 1 u 1 i ik ke e t / va ihe: 50

Shaking intensity: 50! Separation time: 10 min.

: The epidermin-containing elements were combined, evaporated, taken up in water and lyophilized several times under high vacuum. The antibiotic (2.6 g) was shown to be uniform in all studies performed.

During the preparation and isolation of the epidermin, a biological characterization and diffusion assay was used, i.e. spectrum, as well as yield, further processing. and enrichment control. The test was performed in: Zähner and Maas, Biology of Antibiotics (Springer 21 82073

Verlag, Berlin-Heidelberg-New TYork, 1972), in petri dishes from Greiner, Niirtingen, equipped with 6 mm diameter filter discs (Macherey & Nagel, Diiren). The filter discs were moistened with 20 of the test liquid, dried at room temperature on a glass plate and placed on a test bed. The test plates were incubated at 37 ° C and growth inhibition was read after about 16 hours.

The routine test organism was Streptococcus pyogenes ATCC 8668 and, due to its trouble-free handling, Micrococcus luteus ATCC 9341.

Test plates with Streptococcus pyogenes ATCC 8668: The test organism had to be inoculated on boat plates / medium containing mucin from the test plates just before preparation: 500 ml Agar pH 7.4, 160 ml mucin solution (10% w / w), 3.5 ml glucose solution (50% by weight) 70 ml ram 's blood. Incubate for 15-18 hours at 37 ° C and then prepare a saline suspension (E 0.5) and pipette this suspension into 1 ml of 100 ml of medium (medium: peptone 10 g, meat extract 8 g, saline 3 g, Na 2 HPO 2 g, glucose · 10 g in 1 l, pH 7.2). Plates cast in 10 ml aliquots were stored for a few days at 4 ° C.

"Test dishes with Micrococcus luteus ATCC 9341: :: Overnight old culture (medium: peptone 10 g, meat extract 8 g, saline 3 g, Na 2 HPO 2 g, glucose 10 g in 1 l, pH 7.2) diluted to 1.0 extinction at 578 nm 0.25 ml of this suspension was placed in 100 ml of agar and poured into 10 ml plates, which could be stored for several days at 4 ° C.

Test plates for the spectrum of action:: * Test plates with bacteria: 22 82073 a) Aerobically live bacteria:

Von's old cultures were grown in these test media and plates were prepared in the same manner as Micrococcus luteus ATCC 9341 plates.

β) Anaerobically living bacteria:

Precultures of Clostridium pasteurianum ATCC 6013 and Propinibacterium acnes DSM 1897 strains were grown in reagent glasses filled with nutrient solution up to the swabs to displace oxygen. 3 ml of preculture was inoculated with 100 ml of agar and poured into plates in 10 ml portions. Incubation was performed in an anaerobia vessel (BBL-Gas Pak 100, Becton, Dickinson GmbH, Heidelberg) at the optimum temperature in each case.

Test dishes with yeast-like fungi:

Cells were grown in shake culture for 18-20 hours in the test medium used in each case. After counting in a Thoma counting chamber, the test plates were inoculated to a density of 10 μg / ml agar.

Test dishes, fungi and streptomycetes in the river: Test organs were grown with slanted tubes (medium: yeast extract 4 g, house extract 10 g, glucose 4 g 1 1 s) a) at the corresponding temperatures until sporulation. The spores were slurried in 3 ml of saline-Tween 80 (1 drop of Tween: 80 and 100 ml of saline) and poured into test plates.

Epidermin has very good antibacterial efficacy; it is particularly effective against many gram-dense bacteria. The antibacterial effect of epidermin was compared with that of nisin (cf. e.g., DE-A-2,000,818 or GB-B-1,182,156); for some important, clinically relevant organisms, fusidic acid was also included in the comparison. Efficacy was determined using a ma 1jadif fusion extractor and determining the lowest inhibitory concentration.

23 82073 (a) May diffusion test:

The dish diffusion test tested the susceptibility of different microorganisms to epidermin and nisin. Table 2 shows that both antibiotics act almost exclusively on Gram-positive bacteria. Nisin was used in the activity of 40,000 units.

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Table 2; Susceptibility to epidermin and nisin Figures in inhibition zone in mm, concentration 1 mg / ml and 0.5 mg / ml. . .. u,, ,,, Epidermin Nisin

Microorganisms Growing conditions r Temp. Start with 1 0.5 1 0.5

Bacteria

Eubacteriales, _grampositiiviset

Arthrobacter aurescens 27 ° C 5 8 Sp '9 8

Arthrobacter crystallopoietes 27 ° C 5 16 i5 16 15

Arthrobacter globiformis 27 ° C 5 14 12 14 13

Arthrobacter oxydans 27 ° C.5 12 11 11 10

Arthrobacter pascens 27 ° C 5 13 12 14 13

Bacillus cereus 37 ° C 3 8 Mp

Bacillus pumilus 37 ° C 4 14 12 12 10

Bacillus subtilis ATCC 6051 37 ° C 4 12 11 9 8

Bacillus subtilis ATCC 6051 37 ° C 6 17 16 14 li

Bacillus subtilis ATCC 6633 · 37 ° C 4 14 11 9 8

Bacillus subtilis F 24-2 37 ° C 4 13 11 8 Sp: Bacillus subtilis A 14 37 ° C 4 12 10 9 Sp ·; Brevibacterium flavum 37eC 4 11 10. 8 7

Clostridium pasteurianum 30 ° C. 7 17 15 14 13:. Clostridium sporogenes 37 ° C 8 10 9 8 M.p.

Corynebacterium spec. 27 ° C 4 15 13 9 8

Corynebacterium insidiosum 27eC 4 19 17 10 8

Corynebacterium rathayi 27eC 4 14 12 10 9

Micrococcus luteus ATCC 381 27eC 5 10 9

Micrococcus luteus ATCC 9341 2-7eC 2 21 20 17 16

Propionibacterium acnes 17eC 8 22 19 21 18

Sareina lutea 37 ° C 5 15 14 15 14

Staphylococcus aureus Tu 202 37 ° C .4 13 10 10 9. and I · 25 82073

Staphylococcus aureus DSM 683 37 ° C 4 11 9 Sp -

Staphylococcus aureus Pen.res 37 ° C 4 12 11 9 8

Staphylococcus cohnii 37 ° C 2 14 12 9 -

Streptococcus pyogenes 37 ° C 2 22 20 18 17

Eubacteriales, gramnegatid'viset

Proteus mirabilis 37 ° C 4 11 9 · 9 7

Proteus vulgaris 37 ° C · 5 9. 8. 8 Sp

Actinomycetales:

Streptomyces glaucescens 27eC 3 10 8. 10 9

Streptomyces violaceoruber 37 ° C 3 98--

Streptomyces virido- 37 ° C 3 11 10 98 chromogenes (-) indicates no effect;

Sp = slightly ': (b) Minimum inhibitory concentration:. For clinically relevant organisms, the minimum inhibitory concentration I was examined in μg / ml on a microtiter plate in the following medium: 5 ml Na-lactate, 5 g Na 2 SO 4, 0.5 g KH PO 2, 0.1 g MgCl 2, 5 g NH 2 Cl, 10 g g glucose, 50 μg calcium pantothenate, 50 μg thiamine, 0.25 μg folic acid, 5 μg niacin, 25 μg p-aminobenzoic acid, 50 μg pyridoxine hydrochloride, *. 25 ug ribof avalanche, 1000 ml Aqua dest.

- ·

Table 3 shows the minimum concentrations of epidermin, nisin and fusidic acid (μg / ml) for comparison.

The activity of nisin used at that time was 2,500 units.

• · I ·> · 26 82073

Table 3:

Minimum inhibitory concentration,;

Epidermin Fusidic acid Nisin

St. epidermidis WG 99_2_4_128

Sc. pyogenes ATCC 8668_0,125_1_4

Sc. pneumoniae AT CC 6302_2__16_32

Mc. luteus ATCC 15957_ 0.25_Q, 5_16

Mc. luteus ATCC 9341_ ^ 0.06_q, 5_8

Cb. xerosis NCTC 9755__0.125_0.125__16 E. coli ATCC 11775_ 128_> 128_> 128 E. coli ATCC 9637_128_> 128_> 128

Propionib. acnes PC 904_Q, Q6_q, 5_ 32

Propionib. acnes ATCC. 25746 0/25 1 64

The platforms given in Table 2 are described below.

·. After adjusting the pH, the media were autoclaved at 20 °. minutes at 121 ° C.

‘The amounts given relate to 1 1 water. Demineralized water was used in chemically defined media.

Medium: (2) Glucose agar medium:

Peptone 10 g ”, Meat extract 8 g l 'NaC 1 3 g

Na 2 HPO 4 2 g

Glucose 10 g (separately autoclaved) J Agar 20 g pH 7,2 • »t 27 82073 (3) Yeast-m pool substrate:

Yeast extract A g

Malt extract 10 g

Glucose A g

Agar 20 g pH 7.3 (A) Oxoid medium for bacteria: Skin extract 10 g

Peptone 10 g N a C1 3 g

Agar 20 g pH 7,2 (3) Broth 8 g (Di fco)

Agar 20 g pH 7.2 (6) Minirn medium for bacteria (HUTTER et al., 1966): D-glucose 8 g diammonium tartrate A g

NaCl 5 g k2hp ° a 2 g •: MgSO4 x 7 H2O 1 g

CaCl 2 0.2 g *: MnSO 4 x H 2 O 0.01 g

Ferrioxamine Θ 0.02 g

Agar 20 g pH 7,2 • 1 I * 28 8 2 0 7 3 (7) · Substrate for Clostridium pasteurianum: L iha extract 3 g

Yeast extract 3g

Malt extract 3g

Peptone 20 g D-glucose 5 g

Ascorbic acid 0.2 g

Agar 20 g pH 7,0 (8) Brewing thioglycollate medium for Propionibacterium acnes:

Thioglycolate tray AO, 5 g

Agar 20 g pH 7.2

The tolerability of epidermin is very good. No toxic effects could be observed with topical use.

A very great advantage is that the resistant Staphylococcus epidermidis DSM 3U95 mutant has resistance to the epidermin it produces. The strain of NCIB 11536 does not have any such resistance to the small molecule antibiotic it produces.

1 A new clone DSM 3095 was obtained as follows: Adaptation was performed in 100 ml Erlenmeyer flasks equipped with a side tube and containing 10 ml of nutrient solution (Brain Heart Infusion). The starting culture was inoculated with 0.5 ml of a 12 hour old culture. In vials containing increasing epidermin concentrations, · **. 0.5 ml of the well-growing culture given in each case was used as a sine. Growth evaluation was performed photometrically at 578 nm. The culture, which had still grown well in liquid culture at a concentration of 1.0 mg / ml epidermin, was diluted with saline and plated. in a dish containing 0.5 mg / ml epidermin. A comparative 2 »82073 value was plated in a literature known from the literature as NCIB 11536 for a comparison strain diluted with a 12-hour-old culture. After 24 hours of incubation at 37 ° C, the ID'6 diluted adapted culture had 94 single colonies. The undiluted control plate plated on plates containing 0.15 mg / ml epidermin did not increase after 48 hours of incubation. Resistance colonies were selected and rasterized on plates of medium 2. Yield to pre-test by removing 5 mm diameter pieces and testing for activity with Micrococcus luteus strain ATCC 9341, after which the producing clone was tested for stea1 usta 11a.

Comparison of the resistant strain with the strain known from the literature: a.) Minimum inhibitory concentration ma 1jadif in the fusion test ^

The minimum inhibitory concentrations given in Table 4 were obtained from the test plates tended to both strains.

Table 4: Epider (minimum inhibitory concentration in the dish-diffusion test with NCIB 11536 and D5M 3095 * · strains.

Strain ^ μg / ml NCIB 11536 10 DSM 3095> 1000 b.) Growth and yield: ‘‘ The development of growth and yield in both strains was compared] ’in the culture medium (3% meat extract, 2% malt extract, 0.37%

Ca (0H)). See Figure 12.

30 82073

Development of growth: Determination of the number of living organisms Development of yield: Activity against Mcrococcus luteu.s strain ATCC 9341 in the ma 1 diffusion test.

A better yield is observed with a resistant strain.

c.) Sensitivity to epidermin in different stages of growth:

Experiments investigating the producer population's own inhibition by antibiotics j? resistance of the selected clone was performed in a biophotometer (Eppendorf photometer with recirculation machine).

These experiments can be performed in more detail, for example, as follows:

The fresh medium was inoculated with 0.5 ml of a 12-hour-old culture of Staphylococcus epidermidis NCIB 11536 or a selected resistant strain of DMS 3095.

These cultures were allowed to grow to 0.043 extinction at 578 nm (cuvettes with a layer thickness of 1 cm) and then divided into 7.5 ml aliquots into Biophotometer-1 cuvettes (layer thickness 2 cm).

The density of the cell suspension was adjusted in a Biophotometer to 90% transmission. Incubation was performed at 37 ° C and maximally aerated. Epidermin was added as an aqueous solution to the various growth stages.

Using both strains, different concentrations of epidermin were added to the beginning and middle of the logarithmic phase. The results are given in Figures 13 and 14.

At the last concentrations tested, no lysis could be detected in the resistant strain.

5i 82073

The epidermin antibiotic of the invention, as well as the culture medium from which it was isolated, has a bactericidal effect which causes cell lysis.

Due to its bactericidal activity and broad spectrum of activity against gram-positive bacteria, the epidermin polypeptide antibiotic of the invention is particularly effective in treating infections caused by gram-positive bacteria. Epidermin is particularly valuable in combating skin infections such as eczema, pustules, cellulite and especially acne. Tables 2 and 3 have shown very good efficacy against some important strains of Propionibacterium acnes. It can be said that epidermin, which is normally produced by human skin organisms, has better skin protective activity than other conventional antibiotics.

The aforementioned pharmaceutical preparations containing the antibiotic according to the invention together with pharmaceutically customary excipients and carriers can be administered orally, parenterally, enterally or topically. However, such formulations may be, in particular, topical formulations, such as solutions, emulsions, gels, lotions, ointments, creams or ointments. Powders.

:: The following examples illustrate the preparation of such pharmaceutical uses: 32 8 2 0 7 3

Example 2 T he tincture 100 g of tincture contains:

Epidermin 1.0 g

Ethanol (04.5 v / v) 56.0 g of 1,2-propylene glycol 40.0 g

Water, water 1 g 3.0 g

Manufacture:

The epidermin is dissolved in ethanol / 1,2-propylene glycol / water, after which the solution is sterile filtered.

Example 3

Solution 100 g of solution contains: *. Epidermin 1.00 g of 1,2-propylene glycol-alkyldimethylbenzylammonium; chloride Benzalkon 0.15 g: Sorbitan monopalmate (Span 40 ^ ^ 0.40 g (O): Sorbitan macrogol palmate (Tu / een 40 '') 1.20 g Oleic acid dodecyl ester (Cetiol V ^^) 2.40 g Mixture of cetyl and stearyl alcohol (Lanette 0 ^ ^) 1.60 g

Cetyl palmitate 0.80 g

Demineralized water ad 100 g

Preparation:: The above amounts of alkyldimethylbenzylammonium

II

33 82073 chloride, sorbin Lane monopalmitate, sorbimacrogol palmitate, diacid dececyl ester, cetyl and stearyl alcohol and cetyl pyrimate are mixed with 75 ml of water, mixed with a homogeneous solution of epidermin in hydrogen and 1,2-propylene.

Example 4

Gel 10C g of gel contains:

Epidermin 1.0 g

Polyethyl alcohol of lauryl alcohol 11 g (Brij 25 ^ ^ 1.0 g of 1,2-propylene enig 1yk o 11 5.0 g

Acrylic acid polymer gave

Carbopol 934 (1.2 g) p-hydroxybenzoic acid methyl ester 1.6 g p-hydroxybenzoic acid propyl ester 0.4 g. Perfume q.s.

Sodium hydroxide at pH 6.5

Demineralization water ad 100 g

Manufacturing:

The amounts of excipients given are mixed with 75 ml of water; the epidermin is dissolved in a mixture of 1,2-propylene glycol and the remainder of the water and this solution is mixed; the finished gel is further homogenized.

Explanations of the figures

Figure 1: Amino- of the total acid hydrolyzate of epidermin. happokromatogrammi; ninhydrin staining, λ = 570 nm.

* 34 82073

Figure 2: Chirasil-Val-Gas Chromatogram of N-pentafluoropropionylamino acid-n-propyl ester of epididermic acid. Temperature program: 3 min. 85 ° C isotherm, then 4 ° C / min. Down to -200 ° C; carrier gas H 2 (0.92 bar).

Figure 3: Epiderminj.ii U1 / spectrum in water, pH 3 (C = 0.15 mg / ml).

Figure 4: Infrared spectrum of the epidermis in potassium bromiditable.

Figure 5: 1 H-nuclear resonance spectrum of epidermin (20 mg / 0.5 ml N, N-dimethylformamide, 400.16 MHz).

Figure 6: 1 C-nuclear resonance spectrum of epidermin (40 mg / 0.5 ml 12C, 2H-dimethylformamide, 100.6 MHz, 45360 pulse).

Figure 7: HPLC chromatogram of epidermin u Bondapak C: 11a 1a (300x3.9 mm). Mobile phase: A = acetonitrile / 0.01 M KH 2 PO 4 (10/90), B = acetonitrile / 0.01 M KH 2 PO 4 (70/30); linear gradient from 10% Bs to 100%. To B, 30 min, run rate 2 ml / min.

Figure 8: Nuclear C resonance spectrum of the P2 fragment (12 mg / 0.5 ml 211-dimethylformamide, 100.6 MHz, 38300 pulse).

Figure 9: Isolation of epidermin.

Figure 10: Comparison of media based on number of living organisms (solid lines) and activity against Micrococcus luteus strain (dashed lines) A Brain Heart Infusion: 03% meat extract 2% malt extract 0.25% CaCO 2 # 3% meat extract 2% malt extract 0.37 % Ca (OH) 2 35 82073

Figure 11: Permeation flow in 10 liters g pH flow Number of living organisms 0 activity against Streptococcus pyogenes ATCC 8668 strain.

Figure 12: Comparison of a strain known from the literature and a resistant DSM 3095 clone based on the number of living organisms (solid lines) and activity against Micrococcus luteus ATCC 9341 (dashed lines).

0 known strain X resistant clone

Figure 13: Addition of epidermin to the different growth stages of Staphylococcus epidermidis NE iti .11336 strain: Curve 1: normal growth course Curve 2: addition of 10 μg / ml epidermin to the beginning of the logarithmic phase leads to lysis.

Curve 3: 10 μg / ml addition of epidermin in the middle of the logarithmic phase also results in lysis.

Curve 4: addition of 2.5 μg / ml epidermin in the middle of the logarithmic phase leads to growth retardation.

; Figure 14: Addition of epidermin to different growth stages of the resistant DSM 3095 clone: Curve 1: normal growth course, identical to NCIB strain 11536.

Curve 2: logarithmic ♦ increase in epidermin 120 μg / ml. the beginning of the phase slows growth only slightly.

Curve 3: the addition of 360 μg / ml of epidermin in the middle of the logarithmic phase also now only leads to a * slowing of growth.

36 82073

Figure 15: Chirasil-Val gas chromatogram of N-pentafluoropropionyl amino acid n-propyl ester of H H-total hydrolyzate. Temperature program: 3 min. 80 ° C

isotherm, then 4 ° C / min. Up to 200 ° C, carrier gas H 2 O.

Il

Claims (2)

37 82073 1. Nature: colorless powder; 2. Solubility: very soluble in water / glacial acetic acid or methanol / glacial acetic acid mixtures, soluble in lower alcohols, insoluble in chloroform, acetone, diethyl ether, light petroleum; 3. Color reactions with silica gel: ninhydrin, chlorine / TDM (TDM = 4,4'-bis- (dimethylamino) diphenylmethane), orsine / sulfuric acid, anisaldehyde / sulfuric acid. Silica gel prefabricated sheets 60 F254 (Merck). System A: k 1 oroform / methane 1 i / 179s ammonia (2/2/1) RF = 0.73 System B: k 1 chloroform / methano1i / 17¾ ammonia (70/35/10) RF = 0.30 System C: n-butanol / vinegar / water (4/1/1) RF = 0.05 5. HPLC: see Figure 7; 6. Stability: stable pH a1ee11 a 2-7, at higher pH values a sharp decrease in activity occurs; 7. Molecular weight: about 2160 (without anions); 8. Ultraviolet absorption spectrum: in aqueous solution, long-wave maximum 267 nm (Figure 3); 9. Infrared Absorption Spectrum: IR spectrum of a sample in potassium bromide tablets (Figure 4); 10. Nuclear Magnetic Resonance Spectra 1 H-NMR spectrum: Fig. 5, 13 C-NMR spectrum: Fig. 6, characterized in that the strain of Staphylococcus epidermidis DSM 3095 is grown aerobically at 34-37 ° C in a rich nutrient solution containing 2-4% meat extract, 1 to 3% of sugar or sugar 1 elevated, consisting of malt extract and / or maltose, and optionally lactose and / or galactose and / or glucose and / or mannitol and / or g 1 of yserine, and 0.25 to 1 % ka 1 of carbonate or II 39 8 2 0 7 3 0,25 to 0,5% of sodium hydroxide, after removal of the cells and inorganic salts, the culture solution, after isolation of the active substance formed, is either extracted with n-butano-11a at pH 8, the butanol extract is evaporated, the residue is dissolved in methanol and the accompanying lipids are removed from the solution by ether precipitation or treated with acrylic ester or polystyrene-based polymers, whereby the absorbed epidermin is removed; methanol / concentrated hydrochloric acid (99: 1), then the solution is neutralized with ammonia and evaporated in vacuo to separate other small molecule peptides, amino acids and salts by gel chromatography (Sephadex LH-20 methanol / acetic acid). ) followed by Craig amplification countercurrent extraction, first with liquid-liquid extraction of n-butano / acetic acid ester / 0.1 N acetic acid (3: 1: 3) by arranging where the epidermin remains initially, and then the epidermin is isolated in a second extraction with a neutral 2-butano / 0.05 N ammonium acetate (1: 1) system, and the epidermin is isolated from the eluate by freeze-drying as a colorless powder. A method for preparing an antibiotically effective polypeptide called epidermin having the following amino acid composition: Arn (1), Pro (1), Gly (2), Ala (2), Ile (2), Phe (2), Lys (2 ), Lan (2), O-Me-Lan (1), Dhb (1), Tyr (1), S- (2-aminovinyl) -D-cysteine (1) and the following primary structure: meso-lanthionine CH- , - S - CH0 II H-Ile-Ala-NH-CH-CO-Lys-Phe-Ile-NH-CH-CO— (S) (R) CH2-β-.methyl lilanthionine (S) CH- S- CH2 L-NH-CH-CO-Pro-Gly-HN-CH-CO-Ala-Lys- 'V (S) (R) ·. ·. <pH2 mesolanthionine CH CH * - S -CH * f (S) | (Z) -HN-C-CO-Gly-HN-CH-CO-Phe-Asn-HN-CH-CO-Tyr-HN-CH-CO-NH-CH (Z) (S) I (R) II CH2-S to CH S- (2-aminovinyl) -D-cysteine mmm * 38 82073 wherein the halves near the N-terminus of the individual thioether amino acids each have the D-configuration, and the following other parameters: Process according to Claim 1, characterized in that 2 to 4% by weight of meat extract or a mixture of all 20 amino acids in each case at a concentration of 2 g / l or 2 to 4% of the Cas amino acid tryptophan and vitamins such as biotin, nicotinic acid, thiamine are used as the nitrogen source of the fermentation medium. in the presence of the hydrochloride and calcium pantothenate, as carbon sources 1 to 3% by weight of malt extract or maltose, optionally lactose and / or with the addition of galactose and / or mannitol and / or glucose and / or glycerin, 0.25 to 1% by weight of kaxcarbonate or - 0.5% by weight of calcium hydroxide, the pH of the fermentation is adjusted to 6.0 to 7.0 and the development of the yield is monitored by continuous sampling. 40 82073