Biosynthesis biotin

StenF24.35c IstL3 348 10406 Metallo cofactor/biotin biosynthesis... 

Schneider G and Lindqvist Y (2001) Structural enzymology of biotin biosynthesis. EBBS Letters 495, 7-11. 

The first total synthesis of amiclenomycin, an inhibitor of biotin biosynthesis, was completed by A. Marquet and co-workers. In order to prove its structure unambiguously, both the cis and trans isomers were prepared. The L-amino acid functionality was installed by a Strecker reaction using TMSCN in the presence of catalytic amounts of Znla. The resulting O-TMS protected cyanohydrin was exposed to saturated methanolic ammonia solution, which gave rise to the corresponding a-amino nitrile. Enzymatic hydrolysis with immobilized pronase afforded the desired L-amino acid. 

This reaction is analogous to the sulfur insertion reaction involved in biotin biosynthesis, and LipA and BioB show significant sequence similarity [145,146]. 8-Mercapto-octanoic acid and 6-mercapto-octanoic acid are intermediates... 

Biotin biosynthesis BioY/BioMN - biotin transporter... 

The pathway for biotin biosynthesis elucidated in bacteria by application of the mutants technique was proposed by Eisenberg in 1968. ° This pathway, which has never been questioned ever since, is depicted in Figure 2. It has also been shown that the same pathway is present in plants."... 

The genetics and enzymology of biotin biosynthesis have been the subject of a reinforced interest when several industrial companies undertook studies directed toward the production of biotin by fermentation, using recombinant strains. This has stimulated a great deal of work for the identification of the bio genes of many... 

Several extensive reviews on biotin biosynthesis have been published. ° The early work will be summarized to the extent necessary for an independent reading, but we shall focus on the recent results. 

For several years, she studied chemical reaction mechanisms, especially those involving sulfoxide carbanions and their synthetic applications. Then, she turned to mechanistic enzymology. Her main interests concerned steroid isomerases and cytochrome P-450, vitamin K-dependent carboxylations, and biotin biosynthesis. She contributed to the mechanistic understanding of several enzymes of the pathway, namely, amino-oxopelargo-nate synthase, diaminopelargonate aminotransferase, and more importantly biotin synthase. 

Stok, J.E. and J.J. De Voss (2000). Expression, purification, and characterization of Biol A carbon-carbon bond cleaving cytochrome P450 involved in biotin biosynthesis in Bacillus subtilis. Arch. Biochem. Biophys. 384, 351-360. 

Bower, S.G. et al. (1993) Biotin biosynthesis in Bacillus subtilis. Patent US6057136 A, Roche Vitamins. 

The water soluble vitamin, biotin, acts as a cofactor for a set of enzymes that catalyze carboxylation, decarboxylation or transcarboxylation reactions (Moss and Lane, 1971). In plants we have characterized four biotin-containing enzymes each of which catalyze reactions required in lipid metabolic processes. These enzymes are the homomeric and heteromeric isozymes of acetyl-CoA carboxylase (ACCase), methylcrotonyl-CoA carboxylase (MCCase) and geranoyl-CoA carboxylase (GCCase). The studies of these biotin-containing enzymes has led to an interest in biotin biosynthesis, and we have cloned the gene coding for biotin synthase. 

The BI02 gene of A. thaliana is interrupted by five introns. The gene codes for a protein of 379 amino acids, with a predicted molecular mass of 41 kDa. The A. thaliana biotin synthase has an N-terminal extension (compared to the bacterial enzyme), which has features indicating it may act as a mitochondrial transit peptide. This would indicate that biotin biosynthesis occurs within mitochondria of plant cells. Indeed, biotin biosynthesis may be derived from pimelic acid, which may be a product of a mitochondrial fatty acid synthase. In situ analyses of the accumulation of the biotin synthase mRNA indicates that the spatial pattern of accumulation changes during the development of the siliques. Namely, whereas the mRNA is present throughout the... 

Biotin biosynthesis has been mainly studied in bacteria such as Escherichia coli... 

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