African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5230

Full Length Research Paper

A novel poly (L-lactide) degrading thermophilic actinomycetes, Actinomadura keratinilytica strain T16-1 and pla sequencing

Sukhumaporn Sukkhum1,5, Shinji Tokuyama2, Prachumporn Kongsaeree3, Tomohiko Tamura4, Yuumi Ishida4 and Vichien Kitpreechavanich1,6*
1Department of Microbiology, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand. 2Department of Biological chemistry, Faculty of Agriculture, Shizuoka University, Shizuoka 422-8529, Japan. 3Department of Biochemistry, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand. 4Biological Resource Center (NBRC), Department of Biotechnology, National Institute of Technology and Evaluation, Kisarazu 292-0818, Japan. 5Department of Biology, Faculty of Science, Srinakharinwirot University, Bangkok 10110, Thailand. 6Center for Advanced Studies in Tropical Natural Resources, Institute for Advanced Studies and Graduated School, Kasetsart University Bangkok 10900, Thailand.
Email: [email protected]

  •  Accepted: 15 June 2011
  •  Published: 16 September 2011


An actinomycete strain T16-1 demonstrated the maximum poly (L-Lactide)-degrading activity when cultured in basal liquid medium at 50°C. According to 16S rDNA sequence analysis, chemotaxonomic and DNA-DNA hybridization revealed that strain T16-1 belong to the family Thermomonosporaceaegenus Actinomadura. On the basis of phenotypic and phylogenic data, strain T16-1 which is a novel PLA-degrading thermophilic actinomycete was identified as Actinomadura keratinilytica, but the color of its colony on ISP plates, NaCl tolerant and utilization of mannitol, raffinose and arabinose were different. Partial sequence of poly (L-lactide) depolymerase gene from strain T16-1 was demonstrated. The gene consisting of 222 amino acids was related to serine protease from Streptomyces sp. with 43 to 46% identity.


Key words: Actinomadura keratinilytica, cloning, identification, poly (L-lactide).