Molecular Characterization of Extracellular Medium-chain-length Poly(3-hydroxyalkanoate) Depolymerase Genes from Pseudomonas alcaligenes Strains

  • Kim Do Young (Department of Microbiology, School of Bioscience and Biotechnology, Chungnam National University) ;
  • Kim Hyun Chul (Department of Microbiology, School of Bioscience and Biotechnology, Chungnam National University) ;
  • Kim Sun Young (Department of Microbiology, School of Bioscience and Biotechnology, Chungnam National University) ;
  • Rhee Young Ha (Department of Microbiology, School of Bioscience and Biotechnology, Chungnam National University)
  • Published : 2005.06.01

Abstract

A bacterial strain M4-7 capable of degrading various polyesters, such as poly$(\varepsilon-caprolactone)$, poly(3-hydroxybutyrate-co-3-hydroxyvalerate), poly(3-hydroxyoctanoate), and poly(3-hydroxy-5-phenylvalerate), was isolated from a marine environment and identified as Pseudomonas alcaligenes. The relative molecular mass of a purified extracellular medium-chain-length poly(3-hydroxyalkanoate) (MCL-PHA) depolymerase $(PhaZ_{palM4-7})$ from P. alcaligenes M4-7 was 28.0 kDa, as determined by SDS-PAGE. The $PhaZ_{palM4-7}$ was most active in 50 mM glycine-NaOH buffer (pH 9.0) at $35^{\circ}C$. It was insensitive to dithiothreitol, sodium azide, and iodoacetamide, but susceptible to p-hydroxymercuribenzoic acid, N-bromosuccinimide, acetic anhydride, EDTA, diisopropyl fluorophosphate, phenylmethylsulfonyl fluoride, Tween 80, and Triton X-100. In this study, the genes encoding MCL-PHA depolymerase were cloned, sequenced, and characterized from a soil bacterium, P. alcaligenes LB19 (Kim et al., 2002, Biomacro-molecules 3, 291-296) as well as P. alcaligenes M4-7. The structural gene $(phaZ_{palLB19})$ of MCL-PHA depolymerase of P. alcaligenes LB19 consisted of an 837 bp open reading frame (ORF) encoding a protein of 278 amino acids with a deduced $M_r$ of 30,188 Da. However, the MCL-PHA depolymerase gene $(phaZ_{palM4-7})$ of P. alcaligenes M4-7 was composed of an 834 bp ORF encoding a protein of 277 amino acids with a deduced Mr of 30,323 Da. Amino acid sequence analyses showed that, in the two different polypeptides, a substrate-binding domain and a catalytic domain are located in the N-terminus and in the C-terminus, respectively. The $PhaZ_{palLB19}$ and the $PhaZ_{palM4-7}$ commonly share the lipase box, GISSG, in their catalytic domains, and utilize $^{111}Asn$ and $^{110}Ser$ residues, respectively, as oxyanions that play an important role in transition-state stabilization of hydrolytic reactions.

Keywords

References

  1. Bradford, M.M. 1976. A rapid and sensitive method for the quantitation of microorganism quantities of protein utilizing the principle of protein-dye binding. Anal. Biochem. 72, 248-254 https://doi.org/10.1016/0003-2697(76)90527-3
  2. Chung, S.H., G.G. Choi, H.W. Kim, and Y.H. Rhee. 2001. Effect of levulinic acid on the production of poly(3-hydroxybutyrate-co- 3-hydroxyvalerate) by Ralstonia eutropha KHB-8862. J. Microbiol. 39, 79-82
  3. Choi, G.G., M.W. Kim, J.Y. Kim, and Y.H. Rhee. 2003. Production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) with high molar fractions of 3-hydroxyvalerate by a threonine overproducing mutant of Alcaligenes sp. SH-69. Biotechnol. Lett. 13, 632-635
  4. Chun, J. 1995. Computer-assisted classification and identification of actinomycetes. Ph.D. Thesis. University of Newcastle, UK
  5. Dunn, M.J. 1996. Electroelution of proteins from polyacrylamide gels. Methods Mol. Biol. 59, 357-362
  6. Elbanna, K., T. Lütke-Eversloh, D. Jendrossek, H. Luftmann, and A. Steinüchel. 2004. Studies on the biodegradability of polythiester copolymers and homopolymers by polyhydroxyalkanoate (PHA)-degrading bacteria and PHA depolymerases. Arch. Microbiol. 182, 212-225
  7. Foster, L.J.R., S.J. Zervas, R.W. Lenz, and R.C. Fuller. 1995. The biodegradation of poly-3-hydroxyalkanoates, PHAs, with long alkyl substituents by Pseudomonas maculicola. Biodegradation 6, 67-73 https://doi.org/10.1007/BF00702301
  8. Jendrossek, D., A. Schirmer, and H.G. Schlegel. 1997. Recent advances in characterization of bacterial PHA depolymerases, p. 89-101. In G. Eggink, A. Steinbüchel, Y. Poirier, B. Witholt (eds.), Proceedings of International Symposium on Bacterial Polyhydroxyalkanoates. NRC Research Press, Ottawa, Canada
  9. Jendrossek, D. 2001. Microbial degradation of polyesters. Adv. Biochem. Eng. Biotechnol. 71, 293-325 https://doi.org/10.1007/3-540-40021-4_10
  10. Kasuya, K.I., H. Mitomo, M. Nakahara, A. Akiba, T. Kudo, and Y. Doi. 2000. Identification of marine benthic P(3HB)-degrading bacterium isolate and characterization of its P(3HB) depolymerase. Biomacromolecules 1, 194-201 https://doi.org/10.1021/bm9900186
  11. Kim, H.M., K.E. Ryu, K.S. Bae, and Y.H. Rhee. 2000a. Purification and characterization of extracellular medium-chain-length polyhydroxyalkanoate deolymerase from Pseudomonas sp. RY- 1. J. Biosci. Bioeng. 89, 196-198 https://doi.org/10.1016/S1389-1723(00)88737-X
  12. Kim, H., H.S. Ju, and J. Kim. 2000b. Characterization of an extracellular poly(3-hydroxy-5-phenylvalerate) depolymerase from Xanthomonas sp. JS02. Appl. Microbiol. Biotechnol. 53, 323-327 https://doi.org/10.1007/s002530050028
  13. Kim, D.Y., Y.B. Kim, and Y.H. Rhee. 2000c. Evaluation of various carbon substrates for the biosynthesis of polyhydroxyalkanoates bearing functional groups by Pseudomonas putida. Int. J. Biol. Macromol. 28, 23-29 https://doi.org/10.1016/S0141-8130(00)00150-1
  14. Kim, D.Y., J.S. Nam, and Y.H. Rhee. 2002. Characterization of an extracellular medium-chain-length poly(3-hydroxyalkanoate) depolymerase from Pseudomonas alcaligenes LB19. Biomacromolecules 3, 291-296 https://doi.org/10.1021/bm010113q
  15. Kim, H.J., D.Y. Kim, J.S. Nam, K.S. Bae, and Y.H. Rhee. 2003. Characterization of an extracellular medium-chain-length poly(3-hydroxyalkanoate) depolymerase from Streptomyces sp. KJ-72. Antonie van Leeuwenhoek 83, 183-189 https://doi.org/10.1023/A:1023395527073
  16. Kim, D.Y. and Y.H. Rhee. 2003. Biodegradation of microbial and synthetic polyesters by fungi. Appl. Microbiol. Biotechnol. 61, 300-308 https://doi.org/10.1007/s00253-002-1205-3
  17. Klingbeil, B., R.M. Kroppenstedt, and D. Jendrossek. 1996. Taxonomic identification of Streptomyces exfoliatus K10 and characterization of its poly(3-hydroxybutyrate) depolymerase gene. FEMS Microbiol. Lett. 142, 215-221 https://doi.org/10.1111/j.1574-6968.1996.tb08433.x
  18. Laemmli, U.K. 1970. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature 227, 680-685 https://doi.org/10.1038/227680a0
  19. Lageveen, R.G., G.W. Huisman, H. Preusting, P. Ketelaar, G. Eggink, and B. Witholt. 1988. Formation of polyesters by Pseudomonas oleovorans: effect of substrate on formation and composition poly-(R)-3-hydroxyalkanoates and poly-(R)-3- hydroxyalkenoates. Appl. Environ. Microbiol. 54, 2924-2932
  20. Park, J.S., J.Y. Choi, P.M. Joung, S.J. Park, Y.H. Rhee, and K.S. Shin. 2001. Isolation of a medium chain length polyhydroxyalkanoic acids degrading bacterium, Janthinobacterium lividum. J. Microbiol. 39, 139-141
  21. Quinteros, R., S. Goodwin, R.W. Lenz, and W.H. Park. 1999. Extracellular degradation of medium chain length poly($\beta$-hydroxyalkanoates by Comamonas sp.. Int. J. Biol. Macromol. 25, 135-143 https://doi.org/10.1016/S0141-8130(99)00027-6
  22. Ramsay, B.A., I. Saracovan, J.A. Ramsay, and R.H. Marchessault. 1994. A method for the isolation of a microorganism producing extracellular long-side-chain poly($\beta$-hydroxyalkanoate) depolymerase. J. Environ. Polym. Degrad. 2, 1-7 https://doi.org/10.1007/BF02073481
  23. Roberts, J.D., J. Kraut, R.A. Alden, and J.J. Birktoft. 1972. Subtilisin: a stereochemical mechanism involving transition-state stabilization. Biochemistry 11, 4293-4303 https://doi.org/10.1021/bi00773a016
  24. Schirmer, A., D. Jendrossek, and H.G. Schlegel. 1993. Degradation of poly(3-hydroxyoctanoic acid) [P(3HO)] by bacteria: purification and properties of a P(3HO) depolymerase from Pseudomonas fluorescens GK13. Appl. Environ. Microbiol. 59, 1220-1227.
  25. Schirmer, A. and D. Jendrossek. 1994. Molecular characterization of the extracellular poly(3-hydroxyoctanoic acid) [P(3HO)] depolymerase gene of Pseudomonas fluorescens GK13 and of its gene product. J. Bacteriol. 176, 7065-7073. https://doi.org/10.1128/jb.176.22.7065-7073.1994
  26. Steinbüchel, A. and H.E. Valentin. 1995. Diversity of bacterial polyhydroxyalkanoic acids. FEMS Microbiol. Lett. 128, 219-228 https://doi.org/10.1111/j.1574-6968.1995.tb07528.x
  27. Syn, C.K.C. and S. Swarup. 2000. A scalable protocol for the isolation of large-sized genomic DNA within an hour from several bacteria. Anal. Biochem. 278, 86-90 https://doi.org/10.1006/abio.1999.4410