JPH08140666A - New microorganism and degradation of polyester with the same - Google Patents

Abstract

PURPOSE: To provide a method for degrading polyester, capable of degrading an aliphatic and aromatic polyester containing polyethylene glycol and utilizing the degradation products by allowing a specific microorganism mixture to act on the polyester. CONSTITUTION: The symbiotic system consisting of (A) Comamonas acidovorance, e.g. Comamonas acidovorance PAO-N2 (FERM P-14541), having an ability for degrading the aliphatic and aromatic polyester and utilizing the produced phthalic acid and (B) a microorganism belonging to the genus Sphingomonas having an ability for assimilating polyethylene glycol (PEG), e.g. Sphingomonas PAO-K1 (FERM P-14542) capable of assimilating the PEG having an average mol.wt. of <=4000 or a Sphingomonas PAO-N6 (FERM P-14543) capable of assimilating the PEG having an average mol.wt. of <=20000, is prepared and subsequently allowed to act on the polyester. The symbiotic system can degrade the PEG phthalate polyester, can perfectly utilize the degradation products, and is useful for bioreactors, waste water treatments, protein engineering, etc.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention generally relates to a novel microorganism having an excellent polyester decomposing ability, a novel microorganism having an excellent polyethylene glycol (hereinafter referred to as "PEG") decomposing ability, and a symbiotic system of the novel microorganism. To a method for decomposing a polyester, particularly an aromatic polyester. Specifically, the novel microorganism according to the present invention relates to the decomposition of these compounds by utilizing the ability to decompose phthalic acid ester, phthalic acid or PEG, and derivatives thereof, and the acquisition of useful components through the decomposition of these compounds.

[0002]

BACKGROUND OF THE INVENTION Although the decomposition of aliphatic polyesters has hitherto been well known, it has been difficult to decompose aromatic polyesters [Biodegradability]. Polymeric material ",
pp.263-276 (1990), Industrial Research Committee, Tokyo]. Regarding the degradation of high molecular weight PEG, degradation by aerobic symbiotic bacteria or anaerobic bacteria has been reported [F. Kawai, CR
C Ctit. Rev. Biotechnol., 6, 273-307 (1987)]. It has only been reported that it is a bacterium that can assimilate the series (Daiichi Kogyo Seiyaku Co., Ltd.) [M. Tak
euchi, et al., System. Appl. Microbiol., 16,227-23
8 (1993)]. Further, Sphingomonas terrae has a restriction on the condition that it can assimilate PEG only in the coexistence with a bacterium belonging to the genus Rhizobium.

Similarly, there are reports on phthalate-utilizing bacteria [Ryuichiro Kurane, "Bioscience and Industry", 46, 5, pp.3173-3177 (1988); "Microbial Engineering Handbook", pp.477-490 (1990), Asakura Shoten, Tokyo], no report has yet been made regarding bacteria specifically degrading polyester.

[0004]

In view of the background of the above-mentioned prior art, the present inventors have made earnest studies to search for a microorganism having both phthalic acid ester decomposing ability and PEG decomposing ability. As a result, the present application Completed the present invention by isolating bacteria with desired characteristics from mixed culture samples isolated from soil on the site of human Yokkaichi factory and mixed culture samples isolated from soil from fields in Sumiyoshi Ward, Osaka City It was done.

That is, the gist of the present invention is: (1) Comamonas acidvolans, which decomposes aliphatic and aromatic polyesters and has the ability to assimilate phthalic acid; (2) the ability to assimilate polyethylene glycol. A novel microorganism belonging to the genus Sphingomonas; (3) comprising polyethylene glycol, comprising a step of preparing a mixture (symbiotic system) of the microorganisms (1) and (2) and allowing it to act on aliphatic and aromatic polyesters (4) A method for decomposing an aliphatic or aromatic polyester; (4) A method for decomposing a phthalate or phthalic acid, which comprises a step of allowing the microorganism (1) to act on a phthalate and / or phthalic acid; and (5) A polyethylene comprising a step of allowing the microorganism (2) to act on polyethylene glycol and / or a polyethylene glycol derivative. A recall and / or decomposition process of a polyethylene glycol derivative.

Three representative novel microorganisms obtained by the present invention [“N2”, “K1”, and “N”, respectively]
6) was determined to determine the biological characteristics of these novel microorganisms with respect to their bacteriological properties, ie, morphological properties, growth state in culture medium, and physiological properties.

The taxonomic properties were determined with reference to the following documents.

I "Classification and Identification of Microorganisms" (Takeharu Hasegawa, ed.), Academic Society Publishing Center, (1975) II "Chemical Classification Experimental Method for Microorganisms" (Kazuo Komagata, ed.), Academic Publishing Center, (1982) III Barrow GI and Feltham RKA, "Cowan and St
eel's Manual for the Identification of Medical Bact
eria ", 3rd edition (1993), CambridgeUniversity Pre
ss. IV Board RG, Jones D. and Skinner FA, "Identi
fication Methods in Applied and Environmental Micro
biology ", (1992) Society for Applied Bacteriology T
echnical Series 29. Blackwell Scientific. The results of the test are listed below.

Mycological properties of N2

[0010]

[Table 5]

[0011]

[Table 6]

Mycological properties of K1

[0013]

[Table 7]

Mycological properties of N6

[0015]

[Table 8]

The above-mentioned K1 and N6 have the same cell wall fatty acid composition and quinone composition as those of the conventional Sphingomonas macrogoltabidas and Sphingomonas.
In contrast to Terae, N6 had a feature that PEG could be specifically assimilated even by this bacterium alone.

Regarding the properties of each of the above novel microorganisms,
Bergey's Manual of Systemat
ic Bacteriology, Vols. 1-4] and N2 corresponded well with various properties of Comamonas acidovorans, and thus was named Comamonas acidovorans PAO-N2. On the other hand, although K1 and N6 are both coryneform bacteria, no corresponding species was searched for in the manual, but a report on the identification of Sphingomonas spp. By M. Takeuchi et al. [M. Takeuchi,
et al., System. Appl. Microbiol., 16, 227-238 (199
3)] and the disclosure of the document cited as a reference in the same document, it was determined to belong to the genus Sphingomonas and named Sphingomonas PAO-K1 and Sphingomonas PAO-N6, respectively. However, as described above, since K1 and N6 of the present invention are unique in cell wall fatty acid composition, quinone composition, and PEG assimilation ability, they are different from the sphingomonas bacteria disclosed in these references. Considered to be a thing.

The Comamonas acidvolans PAO-N2 and the sphingomonas obtained in the present invention
PAO-K1 and Sphingomonas PAO-N6 were deposited on September 19th, 1994 at the Institute for Microbial Engineering, Ministry of International Trade and Industry, Ministry of International Trade and Industry, 1-3-3 Higashimachi, Tsukuba, Ibaraki. And [under the name of PAO-N2] accession number FERM P-14
541; [under the name of PAO-K1] accession number FERM P-14542;
Accession number FERM P-14543 is given [under the name of PAO-N6], and the present invention contemplates not only these deposited microorganisms but also mutants and progeny thereof having the above-mentioned ability.

Next, an outline of the method for degrading polyester (laboratory scale) in the thus obtained mixed culture system of bacteria will be described. First, in order to correspond to the molecular weight of PEG constituting the polyester, Comamonas・ Choose and prepare Asidovorans PAO-N2 and Sphingomonas PAO-K1 or Sphingomonas PAO-N6. And
As the medium, a basal medium prepared according to the medium composition shown in Table 9 below was used.

[0020]

[Table 9]

After sterilization by adding an appropriate polyester to this basal medium, Comamonas acidovorans PAO
-Inoculate N2 with Sphingomonas PAO-K1 or Sphingomonas PAO-N6 and shake. After shaking culture, the bacterial cells were removed from the culture by centrifugation, and the remaining amount of undegraded substances in the supernatant and degradation products were applied to gel permeation chromatography (hereinafter referred to as "GPC"). And analyze.

The culture conditions should be set within the growth temperature range of the microorganism to be used, preferably within the optimum growth temperature range. However, this range varies depending on the composition of the medium, pH and other conditions. Not specified but usually 10
It is preferable to set the temperature to -30 ° C, preferably 20 to 30 ° C, and to set the pH in the vicinity of neutrality (6.0 to 7.5) in order to prepare good analysis conditions.

The culture conditions are preferably aerobic conditions in order to bring about good growth of the microorganisms, and, for example, a shaking culture method or an aeration-agitation culture method can be used. As the culture time, polyester and PE which is a decomposition product are used.
It may be carried out until G is sufficiently decomposed, and usually 5 to 7 days [PEG4000 polyester and PEG6000 polyester] or 7 to 10 days [PEG20000 polyester (trade name: PAOGEN PP-15 (Daiichi Kogyo Seiyaku Co., Ltd.)] However, in general, it is preferably 7 days or longer and 14 days or longer, respectively.
It is necessary to supplement nutrients sufficient for the growth of microorganisms, and inorganic salts, nitrogen sources, etc. are usually added.

The inorganic salt may be a phosphate, a magnesium salt, a calcium salt or the like, and the nitrogen source may be one that is assimilated in a mixed culture system, such as ammonium sulfate, ammonium phosphate and chloride. Ammonium,
Ammonium nitrate, nitrate and the like are applicable, and one or more of these can be arbitrarily selected and used. Furthermore, an appropriate amount of vitamins, yeast extract or the like can be added as a nutrient source for promoting the growth of microorganisms in the mixed culture system. In the present invention, PEG that can be assimilated by the microorganism used
Alternatively, the reaction can be carried out by adding cells obtained by culturing in advance in a culture solution containing a dialkyl phthalate ester to a liquid having the same composition as the above-mentioned basal medium.

Further, in the present invention, PEG as a carbon source is used.
Or containing a PEG derivative such as a nonionic surfactant, sterilize a medium having the same composition as the above-mentioned basic medium, inoculate it with Sphingomonas PAO-K1 or Sphingomonas PAO-N6, It also includes a mode of shaking culture.

In the present invention, Sphingomonas PAO is also used.
P that can be assimilated by -K1 or Sphingomonas PAO-N6
The reaction can also be carried out by adding cells obtained by pre-culturing in a medium containing EG or a derivative thereof to a liquid having the same composition as that of the basal medium described above.

Further, in the present invention, a medium having the same composition as the above-mentioned basal medium is sterilized using phthalic acid or its ester as a carbon source, and then this is inoculated with Comamonas acidvolans PAO-N2. In the same manner as the above-mentioned Sphingomonas PAO-K1 or PAO-N6, it is pre-cultured in a medium containing a carbon source which can be assimilated by this Comamonas acidovorans PAO-N2. The cells thus obtained can be added to a liquid medium having the same composition as the basal medium to carry out the reaction.

Other aspects and advantages of the present invention will be apparent from the disclosure of the exemplary embodiments shown below.

[0029]

Examples Example 1: Isolation of strain As a single carbon source of the above-mentioned basic medium, PEG4000 [trade name: PEG series (Daiichi Kogyo Seiyaku Co., Ltd.)] phthalic acid polyester or PEG6000 [trade name: PEG]
Series (Daiichi Kogyo Seiyaku Co., Ltd.)] A mixed culture sample separated from the soil on the premises of the applicant's Yokkaichi plant as described above in a basic medium having the above-mentioned composition containing polyester phthalate, and Sumiyoshi-ku, Osaka Collected from all over Japan, including mixed culture samples separated from the soil of the fields in
The above-mentioned culture medium was inoculated with a water suspension supernatant of 268 soil samples and a supernatant obtained by acclimatizing 4 types of activated sludge samples obtained from a sewage treatment plant.

[0030] and, by the turbidity of the medium due to the growth of the bacteria was observed sample a conventional method (disclosure of "microbial engineering technology Handbook", supra), an integrated culture, it was repeated several times.
As a result, good growth was observed for 15 soil samples. Furthermore, as the bacteria which finally showed the best growth, one kind from the medium using PEG4000 phthalate polyester (mixed culture system K) and one kind from the medium using PEG6000 phthalate polyester (mixed culture system K) N) were selected respectively. By purely separating the bacteria involved in the degradation and assimilation of polyester from each culture system, in culture system K, Comamonas acidovorans PAO-N2 and Sphingomonas PAO-K1 were added to culture system N. Found that Comamonas acidovorans PAO-N2 and Sphingomonas PAO-N6 are contained in the mycological analysis results.

Example 2: Polyester resolution [Polyester ]
As a single carbon source of the basic medium described above, 100 ml of a medium containing PEG4000 was placed in a 500 ml Sakaguchi flask (shaking flask 4070 FK-500: Iwaki glass). Then, this medium was sterilized by heating in an autoclave [Autoclave S-90-N: Tommy Seiko] for 15 minutes at 120 ° C, and then several platinum loops of Sphingomonas PAO-K1 were inoculated into this medium, The culture was performed with shaking (105 reciprocations / min) in a reciprocating shake cultivator [reciprocating shake cultivator RLR-3: Iwashiya Biological Science Co., Ltd.] at 3 ° C. for 3 to 4 days [Preculture 1]. Also, Comamonas acidovorans PAO-N2
Were cultured in a dibutylphthalic acid (0.2%: DBP) medium in the same manner as in the case of Sphingomonas PAO-K1 [preculture 2]. On the other hand, instead of pre-culture 1 and 2,
Sphingomonas PAO-K1 and Comamonas acidovorans PAO-N2 were used as the sole carbon source of basal medium for PEG40.
A mixture of 00 phthalate polyester medium and several platinum loops was mixed and inoculated, and the mixture was cultured according to the method described above, and this was used as preculture [Preculture 3].

Next, the basal medium prepared by changing the concentration of PEG4000 polyester was sterilized by heating in an autoclave [Autoclape S-90-N: Tommy Seiko] for 5 minutes at 120 ° C. 5 ml of the culture obtained in culture 3
Was inoculated into this medium and shaken at 30 ° C for 3 days (105
(Round trip / min) Culture was performed.

The obtained culture broth was subjected to 9000 rpm for 20 minutes.
Centrifuge [High-speed cooling centrifuge 20PR-52: Hitachi Koki]
Then, the supernatant was applied to GPC and analyzed.
The measurement conditions using GPC are as follows.

Equipment used: Tosoh high-speed GPC device HLC
-8020 Column: Tosoh TSHGEL G5000PW _XL -G4000PW _XL -G30
00PW _XL -G2500PW _XL (inner diameter: 7.8 mm, length: 30 cm) Solvent: 0.1 M sodium chloride (flow rate: 0.7 ml / min.,
(Temperature: 40 ° C.) Detector: RI (differential refractive index) detection The analysis results are shown in Table 10 below.

[0035]

[Table 10]

Example 3: Polyester resolution [cultivation days
Dependency] 100 ml of a medium prepared in the same manner as in Example 2 and having a PEG4000 polyester concentration of 0.5% was placed in a 500 ml Sakaguchi flask and sterilized by autoclaving. Then, 5 ml of the culture obtained in Preculture 3 precultured in the same manner as in Example 2 was inoculated into this medium and shaken at 30 ° C. (105
(Round trip / min) Culture was performed.

The growth rate of the bacteria grown by this culture is the absorbance at λ = 610 nm, and the carbon source decomposition rate is the same as the GPC measurement conditions in Example 2 under the same GPC measurement conditions.
The results are shown in Table 11 below.

[0038]

[Table 11]

Example 4: Polyester resolution [Polyes]
Tell Concentration Dependence] Preculture of Sphingomonas PAO-K1 [Preculture 4] according to the method described in Example 2 except that PEG6000 was used as the single carbon source of the basic medium described above. , Preculture of Comamonas acidovorans PAO-N2 [preculture 5] and mixed culture of Sphingomonas PAO-K1 and Comamonas acidovorans PAO-N2 [preculture 6] were performed.

Next, the basal medium prepared by changing the concentration of the PEG6000 polyester was autoclaved at 120 ° C. for 5 minutes in the same manner as in Example 2 (autoclave S-90-N: Tommy Seiko). ] Was sterilized by heating, and 5 ml of the culture obtained in Preculture 6 was inoculated into this medium, and at 30 ° C,
Shaking (105 reciprocations / min) culture was performed for 7 days. The obtained culture solution was centrifuged at 9000 rpm for 20 minutes [high-speed cooling centrifuge 20PR-52: Hitachi Koki Co., Ltd.]
It was applied to PC and analyzed. The GPC measurement conditions were the same as in Example 2. The analysis result
The results are shown in Table 12 below.

[0041]

[Table 12]

Example 5: Polyester resolution [number of culture days
Dependency] 100 ml of a medium prepared in the same manner as in Example 4 and having a PEG6000 polyester concentration of 0.5% was placed in a 500 ml Sakaguchi flask and autoclaved. Then, 5 ml of the culture obtained in Preculture 6 precultured in the same manner as in Example 4 was inoculated into this medium, and cultivated with shaking (105 reciprocations / minute) at 30 ° C. The growth rate of the bacteria grown by this culture was the absorbance at λ = 610 nm, and the carbon source decomposition rate was analyzed by GPC. The results are shown in Table 13 below.
It was shown to. The GPC measurement conditions were the same as in Example 2.

[0043]

[Table 13]

Example 6: Polyester resolution [number of culture days
Dependency] assay 10 ml of the culture obtained in Preculture 2 was added to 100 ml of the above basal medium containing 0.5% of PEG 20000 polyester for 30
After culturing with shaking (105 reciprocations / minute) for 1 day at ℃, this culture suspension was centrifuged at 9000 rpm for 20 minutes to remove the cells, and the resulting culture supernatant was sterilized by filtration. did.
Then, GPC analysis was performed on the substrate and the amount of PEG produced in the culture filtrate under the same conditions as in Example 2, and it was found that all of the polyester had been decomposed into PEG 20000 (data not shown). On the other hand, Sphingomonas PAO-N was prepared according to the method described in Example 2 except that PEG 20000 was used as the single carbon source of the basal medium.
6 precultures [preculture 7] were performed. Then, 10 ml of the culture obtained in Preculture 7 was added to the culture supernatant sterilized by filtration.
Were inoculated and cultured at 30 ° C. for 15 days with shaking (105 reciprocations / minute). Then, the culture solution was collected on the 8th and 15th days after the start of the culture, and the growth rate of the bacteria propagated by this culture was measured by the absorbance at λ = 610 nm, and the PEG in the supernatant solution from which the bacterial cells had been removed was obtained. Under the same conditions as in Example 2, G
Analysis was performed by PC, and the results are shown in Table 14 below. After the analysis on the 8th day, the pH of the reaction solution was adjusted to 7.0 with 1N sodium hydroxide.

[0045]

[Table 14]

Example 7: Polyester resolution [Polyes]
Ter Species Dependence] Comamonas acidovorans PAO-N2 culture grown for 3 days in a basic medium containing 0.2% dibutylphthalic acid (DBP) was centrifuged at 9000 rpm for 20 minutes. Add 0.5% PEG40 to the supernatant or cells obtained by separation.
00 or phthalic acid polyester, PEG4000 and isophthalic acid polyester, or PEG4000 and terephthalic acid polyester, and a phosphate buffer solution so that the final concentration of the reaction solution is 0.05M.
(pH 7.0) was added and the reaction was allowed to proceed at 30 ° C. After starting this reaction, the degradation of the substrate on the first and third days was analyzed by GPC under the same conditions as in Example 2, and the results are shown in Table 15 below.

[0047]

[Table 15]

Example 8: Polyester resolution [Polyester ]
Ter Species Dependence] Comamonas acidovorans PAO-N2 culture grown for 3 days in a basic medium containing 0.2% dibutylphthalic acid (DBP) was centrifuged at 9000 rpm for 20 minutes. In the supernatant obtained by separation, a polyester composed of PEG4000 and phthalic acid (DMPPAO), a polyester composed of PEG4000 and isophthalic acid at a concentration of 0.5% (DMIPAO),
Alternatively, one of polyesters (DMTPAO) composed of PEG4000 and terephthalic acid was used as a reaction substrate. Then, as enzymes acting on these substrates, in addition to the culture supernatant of Comamonas acidovorans PAO-N2, esterase (100U) [ Pseudomonas sp. Origin: A. Sugihara
et al., Biosci. Biotech. Biochem. 58 , 752-755 (199
4)], lipase (7000U) [ Candida cy
lindracea origin: Meito Sangyo Co., Ltd.], lipase (11U)
(Derived from Fusarium sp . : Y. Shimada et al., J. Ferment.
Bioeng., 75 , 349-352 (1993)], and lipase (500U) [from Rhizopus arrhizus : Sigm
aChemical, St. Louis, USA] was prepared. Then, a phosphate buffer solution (pH 7.0) was added so that the final concentration of the reaction solution was 0.05 M, and the reaction was allowed to proceed. After this reaction was allowed to proceed at 30 ° C. for 3 days, the decomposition of the substrate was analyzed by GPC under the same conditions as in Example 2, and the results are shown in Table 16 below.

[0049]

[Table 16]

Example 9: Polyester resolution [Polyes]
Ter Species Dependence] Comamonas acidovorans PAO-N2 culture grown for 3 days in a basic medium containing 0.2% dibutylphthalic acid (DBP) was centrifuged at 9000 rpm for 20 minutes. The supernatant or cells obtained by the separation were added with 0.5% concentration of (1) PEG4.
000 and phthalic acid polyester, (2) PEG6000 and phthalic acid polyester, (3) PEG20000 and phthalic acid polyester [Product name: PAOGEN PP-15 (Daiichi Kogyo Seiyaku Co., Ltd.)], (4) PEG9000-PEG2000-PEG9000
Polyester consisting of and phthalic acid [Product name: PAOGEN EP-
15 (Daiichi Kogyo Seiyaku Co., Ltd.)] and (5) PEG 20000 and a polyester composed of sebacic acid [fatty acid] are added, and a phosphate buffer solution (pH 7.0) is added so that the final concentration of the reaction solution becomes 0.05M. Was added to allow the reaction to proceed. The reaction was allowed to proceed at 30 ° C. for 3 days, and the decomposition of the substrate at that time was analyzed by GPC under the same conditions as in Example 2. The results are shown in Table 17 below.

[0051]

[Table 17]

[0052]

INDUSTRIAL APPLICABILITY According to the present invention, in addition to specifically decomposing phthalic acid ester, isophthalic acid ester and terephthalic acid ester, phthalic acid, which is a decomposition product, can be utilized
Comamonas acidovorans PAO-N2; and PE
Sphingomonas P that can utilize G or its derivatives
New microorganisms of AO-K1 and Sphingomonas PAO-N6 are provided.

That is, these novel microorganisms provided by the present invention can not only decompose the polyester and assimilate PEG in a growth medium containing the above-mentioned polyester and PEG as a carbon source, By mixing and culturing the microorganisms, the PEG phthalate polyester can be efficiently decomposed, and the decomposition products can be completely assimilated and decomposed. In addition, considering these effects of the present invention, a bioreactor,
A wide range of applications in the fields of wastewater treatment, protein engineering, etc. are of course promising.

Claims (20)

[Claims] 1. A Comamonas acidvolans, which is capable of decomposing aliphatic and aromatic polyesters and having an ability to assimilate phthalic acid. 2. The Comamonas acidovorans of claim 1, wherein the polyester comprises a polyester selected from the group consisting of phthalic acid, isophthalic acid, terephthalic acid, and combinations thereof. 3. The Comamonas acidovorans
The following mycological properties, namely; [Table 2] The Comamonas acidovorans according to claim 1 or 2, which has the mycological properties of: 4. The Comamonas acidovorans is
Comamonas acidovorans PAO-N2 (PAO-N2: FERM
P-14541), The Comamonas acidovorans according to claim 3. 5. A novel microorganism belonging to the genus Sphingomonas, which is characterized by having an ability to assimilate polyethylene glycol. 6. The novel microorganism belonging to the genus Sphingomonas according to claim 5, wherein the polyethylene glycol is a polyethylene glycol having an average molecular weight of 4,000 or less. 7. The novel microorganism belonging to the genus Sphingomonas has the following mycological properties: The novel microorganism belonging to the genus Sphingomonas according to claim 6, which has the mycological properties of. 8. The novel microorganism belonging to the genus Sphingomonas is Sphingomonas PAO-K1 (PAO-K1: FERM P-1
4542), which is a novel microorganism belonging to the genus Sphingomonas according to claim 7. 9. The novel microorganism belonging to the genus Sphingomonas according to claim 5, wherein the polyethylene glycol is polyethylene glycol having an average molecular weight of 20,000 or less. 10. The novel microorganism belonging to the genus Sphingomonas has the following mycological properties: The novel microorganism belonging to the genus Sphingomonas according to claim 9, which has the mycological properties of. 11. The novel microorganism belonging to the genus Sphingomonas is Sphingomonas PAO-N6 (PAO-N6: FERM P
-14543), the novel microorganism belonging to the genus Sphingomonas according to claim 10. 12. A method for decomposing aliphatic and aromatic polyesters containing polyethylene glycol, which comprises the following steps: Decomposing aliphatic and aromatic polyesters and having phthalic acid assimilation ability. And a mixture of novel microorganisms belonging to the genus Sphingomonas capable of assimilating polyethylene glycol, and allowing the mixture to act on aliphatic and aromatic polyesters, polyethylene glycol Method for decomposing aliphatic and aromatic polyesters containing. 13. The Comamonas acidovorans PAO-N2 (PAO-N2:
FERM P-1454 1) The method for decomposing aliphatic and aromatic polyesters containing polyethylene glycol according to claim 12. 14. The novel microorganism belonging to the genus Sphingomonas is Sphingomonas PAO-K1 (PAO-K1: FERM P
-14542), The method for decomposing aliphatic and aromatic polyesters containing polyethylene glycol according to claim 12. 15. The novel microorganism belonging to the genus Sphingomonas is Sphingomonas PAO-N6 (PAO-N6: FERM P
-14543), The method for decomposing aliphatic and aromatic polyesters containing polyethylene glycol according to claim 12. 16. A method for decomposing a phthalic acid ester and / or a phthalic acid, which comprises the following steps: decomposing an aliphatic and aromatic polyester with a phthalic acid ester and / or phthalic acid and assimilating phthalic acid. A method for decomposing phthalic acid ester or phthalic acid, which comprises the step of acting on comamonas acidvolans having ability. 17. The comamonas acidvolans PAO-N2 (PAO-N2:
FERM P-1454 1) The method for decomposing phthalic acid ester or phthalic acid according to claim 16. 18. A method for decomposing polyethylene glycol and / or a polyethylene glycol derivative, which comprises the following steps; ie, applying the polyethylene glycol and / or the polyethylene glycol derivative to a novel microorganism belonging to the genus Sphingomonas having an ability to utilize polyethylene glycol. A method for decomposing polyethylene glycol and / or a polyethylene glycol derivative, which comprises the step of: 19. The novel microorganism belonging to the genus Sphingomonas is Sphingomonas PAO-K1 (PAO-K1: FERM P
-14542) The method for decomposing polyethylene glycol and / or polyethylene glycol derivative according to claim 18. 20. The novel microorganism belonging to the genus Sphingomonas is Sphingomonas PAO-N6 (PAO-N6: FERM P
-14543), The method for decomposing polyethylene glycol and / or polyethylene glycol derivative according to claim 18.