The genes encoding two subunits of acetyl coenzyme A carboxylase, biotin carboxyl carrier protein, and biotin carboxylase have been cloned from Bacillus subtilis. DNA sequencing and RNA blot hybridization studies indicated that the B. subtilis accB homolog which encodes biotin carboxyl carrier protein, is part of an operon that includes accC, the gene encoding the biotin carboxylase subunit of ...

A homogeneous enzyme-linked competitive-binding assay for biotin with glucose-6-phosphate dehydrogenase (GGPDH), is described. This assay is based on the interaction between a GGPDH/biotin conjugate with avidin, a natural binder for biotin. In the absence of biotin in the assay mixture, this interaction results in 100% inhibition of the enzyme conjugate. In the presence of biotin, the enzymatic...

Endogenous biotin or biotinylated protein binding activity is a major drawback to biotin-avidin/streptavidin detection system. The avidin/streptavidin conjugate used to detect the complex of the biotinylated secondary antibody and the primary antibody binds to endogenous biotin or biotinylated proteins leading to non-specific signals. In Western blot, the endogenous biotin or biotinylated prote...

The essential vitamin biotin is a covalent and tenaciously attached prosthetic group in several carboxylases that play important roles in the regulation of energy metabolism. Here we describe increased acetyl-CoA levels and mitochondrial hyperacetylation as downstream metabolic effects of biotin deficiency. Upregulated mitochondrial acetylation sites correlate with the cellular deficiency of th...

The transport of [(14)C]biotin into cells of a biotin prototroph, Escherichia coli K-12 strain Y10-1, was investigated. The vitamin taken up by the cells in this strain existed primarily in the free form. Addition of glucose enhanced the rate of uptake six- to eightfold and the steady level was reached in 2 to 3 min resulting in accumulation of biotin against a concentration gradient. The uptak...

Biotin deficiency in chicks has been reported to result in a marked decrease in the synthesis of albumin and in the activity of amylase (3). Kritsman, Konikova, and Yukhnovskaya (4) observed that the incorporation of methionine-S3s into the proteins of biotin-deficient rats was reduced as compared to the normal animals. Studies in vitro gave similar results; also, the addition of biotin to the ...

Biotin affects the abundance of mRNA coding for 10% of genes expressed in human-derived hepatocarcinoma (HepG2) cells. Here, we determined whether effects of biotin on gene expression are associated with changes in the abundance of distinct proteins in cell signaling and structure. HepG2 cells were cultured in media containing the following concentrations of biotin: 0.025 nmol/L (denoted “defic...

A number of microorganisms have been investigated which require some particular fatty acid in addition to biotin as a growth factor (l-6). On the other hand, a large group of organisms are able to utilize certain fatty acids in place of biotin in the medium (7-11). Axelrod and coworkers (12, 13) reported that the saponifiable fraction from blood plasma possesses high biotin activity. This extra...

It has been well established that human intestinal and liver epithelial cells transport biotin via an Na+-dependent carrier-mediated mechanism. The sodium-dependent multivitamin transport (SMVT), a biotin transporter, is expressed in both cell types. However, the relative contribution of SMVT toward total carrier-mediated uptake of physiological (nanomolar) concentrations of biotin by these cel...