title: The amino acid requirements of Corynebacterium diphtheriae PW 8 substrain CN 2000.
abstract: OBJECTIVE
  To determine the amino acid requirement and utilization pattern of Corynebacterium diphtheriae during growth and toxin production.
  
  
  RESULTS
  Comparing across different batches of beef-based media, the growth and toxin yield were correlated significantly with nine of the amino acids. The amino acid utilization pattern during growth of C. diphtheriae further showed that only four of the nine amino acids, namely cystine, histidine, aspartate and methionine, were critical for growth of the vaccine strain. Further investigations using synthetic media with combinations of amino acid supplements demonstrated that among the four, cystine was the most growth limiting.
  
  
  CONCLUSIONS
  Only certain amino acids are critical for growth and toxin production by C. diphtheriae, cystine being the single most important.
  
  
  CONCLUSIONS
  Owing to the potential threat from Bovine Spongiform Encephalopathy (BSE), a need is recognized by vaccine manufacturers to substitute beef-based production media. An understanding of the specific amino acid requirements would help to develop and optimize alternative production media.
authors.affiliation: Serum Institute of India, Research Foundation, Pune, India, Department of Microbiology, Abasaheb Garware College, Pune, India.
authors.forename: P P
authors.initials: PP
authors.lastname: Nagarkar
authors.forename: S D
authors.initials: SD
authors.lastname: Ravetkar
authors.forename: M G
authors.initials: MG
authors.lastname: Watve
mesh_terms: D000596:Amino Acids / Q000032:analysis*; D003353:Corynebacterium diphtheriae / Q000254:growth & development*; D003470:Culture Media / Q000737:chemistry; D003553:Cystine / Q000032:analysis; D004167:Diphtheria Toxin / Q000096:biosynthesis; D005285:Fermentation
chemical_list: D000596:Amino Acids; D003470:Culture Media; D004167:Diphtheria Toxin; D003553:Cystine