In order to identify antigenic proteins of

No abstract

The bioconversion of dethiobiotin to biotin has been demonstrated by cell‐free extracts of a biotin‐hyperproducing Bacillus sphaericus mutant transformed with an expression vector for two bio genes: bioB, encoding biotin synthase; and bioY, the function of which remains unknown. The reaction mixture for the biosynthesis of biotin contained yeast extract, l‐cysteine and sucrose as well as dethiobiotin. The cell‐free extracts prepared from protoplasts of the transformant with a French press at not more than 1000 kg cm−2 showed appreciable biotin synthase activities. An unusually high protein concentration (more than 18 mg ml−1) in the reaction mixture was required for the enzyme activity, while cell‐free extracts of less than 10 mg protein ml−1 hardly exhibited detectable activities. The product from dethiobiotin in a reaction mixture was identified as biotin by bioautography with Lactobacillus plantarum.

No abstract

The bioconversion of dethiobiotin to biotin has been demonstrated by cell‐free extracts of a biotin‐hyperproducing Bacillus sphaericus mutant transformed with an expression vector for two bio genes: bioB, encoding biotin synthase; and bioY, the function of which remains unknown. The reaction mixture for the biosynthesis of biotin contained yeast extract, l‐cysteine and sucrose as well as dethiobiotin. The cell‐free extracts prepared from protoplasts of the transformant with a French press at not more than 1000 kg cm−2 showed appreciable biotin synthase activities. An unusually high protein concentration (more than 18 mg ml−1) in the reaction mixture was required for the enzyme activity, while cell‐free extracts of less than 10 mg protein ml−1 hardly exhibited detectable activities. The product from dethiobiotin in a reaction mixture was identified as biotin by bioautography with Lactobacillus plantarum.