African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5232

Full Length Research Paper

Production and optimization of D-amino acid oxidase which is involved in the biosynthesis of β-lactam antibiotics

A. Saleem1*, A. M. Moharram2 and N. Fathy3      
1Department of Botany, Faculty of Science, South Valley University, Qena, Egypt. 2Department of Botany, Faculty of Science, Assuit University, Assiut, Egypt. 3Department of Microbiology, Hebi Company for Pharmaceutical Industries, Egypt.  
Email: [email protected]

  •  Accepted: 10 January 2012
  •  Published: 30 May 2012

Abstract

A total of sixty seven fungal isolates representing 40 fungal species related to 14 genera were screened for their abilities to produce endocellular D-amino acid oxidase enzyme. The most active fungal isolates were Fusarium heterosporum and Nectria haematococca, producing 210.41 and 207.94 units/ml, respectively. Maximum activity of D-amino acid oxidase produced by F. heterosporum and N. haematococca was obtained after 7 days of incubation at 30°C with pH 7 culture medium containing glucose and ammonium sulphate as carbon and nitrogen sources, respectively. Inoculation of cultures by 3 discs of fungi and incubation of cultures at 160 rpm shaking condition improved the enzyme production. Among seven amino acids tested, D-alanine was the best inducer for D-amino acid oxidase production by F. heterosporum; however L-asparagine was the best by N. haematococca.High-performance liquid chromatography (HPLC) analysis indicated that the purified D-amino acid oxidase produced by both fungi was active for the conversion of cephalosporin C to glutaryl-7-aminocephalosporanic acid. 

 

Key words: D-amino acid oxidase, antibiotic biosynthesis, Fusarium heterosporum,Nectria haematococca.