Growth factor requirement ofThiobacillus novellus

✍ Scribed by A. Matin; F. J. Kahan; R. H. Leefeldt

• Book ID: 104760928
• Publisher: Springer
• Year: 1980
• Tongue: English
• Weight: 416 KB
• Volume: 124
• Category: Article
• ISSN: 0302-8933
• DOI: 10.1007/bf00407034

✦ Synopsis

Thiobacillus novellus c a n n o t be grown in mineral salts media unless supplied with yeast extract. The requirement is only for miniscule a m o u n t s of yeast extract and is not fully expressed unless cells grown in a complex m e d i u m are allowed to multiply in a mineral salts m e d i u m for four to five generations. Individual sulfur-containing organic compounds, namely biotin, coenzyme A, a n d lipoic acid, b u t not reduced inorganic sulfur compounds, can substitute for the yeast extract requirement. Biotin can fully satisfy this requirement at a concentration insufficient to fulfill the biosynthetic sulfur needs; further, the organisms continue to incorporate 35SO4 into cellular protein in the presence of yeast extract or biotin. It is concluded that biotin is required as a growth factor and not owing to an inability to obtain sulfur from sulfate; the reasons why coenzyme A a n d thiamine pyrophosphate can substitute for biotin are discussed.