Isolation and Characterization of Polyester-Based Plastics-Degrading Bacteria from Compost Soils
- 32 Downloads
Four potential polyester-degrading bacterial strains were isolated from compost soils in Thailand. These bacteria exhibited strong degradation activity for polyester biodegradable plastics, such as polylactic acid (PLA), polycaprolactone (PCL), poly-(butylene succinate) (PBS) and polybutylene succinate-co-adipate (PBSA) as substrates. The strains, classified according to phenotypic characteristics and 16S rDNA sequence, belonging to the genera Actinomadura, Streptomyces and Laceyella, demonstrated the best polyester- degrading activities. All strains utilized polyesters as a carbon source, and yeast extract with ammonium sulphate was utilized as a nitrogen source for enzyme production. Optimization for polyester-degrading enzyme production by Actinomadura sp. S14, Actinomadura sp. TF1, Streptomyces sp. APL3 and Laceyella sp. TP4 revealed the highest polyester-degrading activity in culture broth when 1% (w/v) PCL (18 U/mL), 0.5% (w/v) PLA (22.3 U/mL), 1% (w/v) PBS (19.4 U/mL) and 0.5% (w/v) PBSA (6.3 U/mL) were used as carbon sources, respectively. All strains exhibited the highest depolymerase activities between pH 6.0–8.0 and temperature 40–60°C. Partial nucleotides of the polyester depolymerase gene from strain S14, TF1 and APL3 were studied. We determined the amino acids making up the depolymerase enzymes had a highly conserved pentapeptide catalytic triad (Gly-His-Ser-Met-Gly), which has been shown to be part of the esterase-lipase superfamily (serine hydrolase).
KeywordsActinomyces depolymerase degradation polyester thermophilic bacteria
Unable to display preview. Download preview PDF.
- Akutsu-Shigeno, Y., Teeraphatpornchai, T., Teamtisong, K., Nomura, N., Uchiyama, H., Nakahara, T., and Nakajima-Kambe, T., Cloning and sequencing of a poly(DL-lactic acid) depolymerase gene from Paenibacillus amylolyticus strain TB-13 and its functional expression in Escherichia coli, Appl. Environ. Microbiol., 2003, vol. 69, pp. 2498–2504.CrossRefPubMedPubMedCentralGoogle Scholar
- Kieser, T., Bibb, M.J., Buttner, M.J., Chater, K.F., and Hopwood, D.A., Practical Streptomyces Genetics, Norwich: The John Innes Foundation, 2000.Google Scholar
- Lane, D.J., 16S/23S rRNA sequencing, in Nucleic Acids Techniques in Bacterial Systematics, Stackebrandt, E. and Goodfellow, M., Eds., Wiley, 1991, pp. 115–147.Google Scholar
- Shinozaki, Y., Morita, T., Cao, X.H., Yoshida, S., Koitabashi, M., Watanabe, T., Suzuki, K., Sameshima-Yamashita, Y., Nakajima-Kambe, T., Fujii, T., and Kitamoto, H.K., Biodegradable plastic-degrading enzyme from Pseudozyma antarctica: cloning, sequencing, and characterization, Appl. Microbiol. Biotechnol., 2013. vol. 97, pp. 2951–2959.CrossRefPubMedGoogle Scholar
- Staneck, J.L. and Roberts, G.D., Simplified approach to identification of aerobic actinomycetes by thin-layer chromatography, Appl. Microbiol., 1994, vol. 28, pp. 226–231.Google Scholar
- Sukkhum, S., Tokuyama, S., Kongsaeree, P., Tamura, T., Ishida, Y., and Kitpreechavanich, V., A novel poly (L-lactide) degrading thermophilic actinomycetes, Actinomadura keratinilytica strain T16-1 and pla sequencing, Afr. J. Microbiol. Res., 2011, vol. 5, pp. 2575–2582.Google Scholar
- Techapun, C., Charoenrat, T., Watanabe, M., Sasaki, K., and Poosaran, N., Optimization of thermostable and alkaline-tolerant cellulose-free xylanase production from agricultural waste by thermotolerant Streptomyces sp. Ab106, using the central composite experimental design, Biochem. Eng. J., 2002, vol. 12, pp. 99–105.CrossRefGoogle Scholar