PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 5344105

Biological studies with alpha-dehydrobiotin.

L J Hanka·L M Reineke·D G Martin
View original source ↗Export metadata ↓

Abstract

A growing culture of Streptomyces lydicus converted biotin-(14)C to alpha-dehydrobiotin-(14)C. The conversion was demonstrated by isolating crystalline alpha-dehydrobiotin-(14)C from fermentation liquors supplemented with biotin-(14)C. The addition of pimelic acid-(14)C to the growing culture did not produce any radioactive alpha-dehydrobiotin. alpha-Dehydrobiotin did not substitute for biotin in Lactobacillus plantarum or in Saccharomyces cerevisiae. Antimicrobial activity of alpha-dehydrobiotin was abolished by avidin. alpha-Dehydrobiotin appears to be different from several biotin vitamers described in the literature. It is concluded that alpha-dehydrobiotin is a product of biotin catabolism in S. lydicus.

Explore related subjects

BiotinCarbon IsotopesChemical PhenomenaChemistryChromatography, PaperCrystallizationCulture MediaFermentationLactobacillusOvalbuminPimelic AcidsSaccharomycesStreptomycesJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

L J Hanka, L M Reineke, D G Martin. 1969. Biological studies with alpha-dehydrobiotin.. https://doi.org/10.1128/jb.100.1.42-46.1969

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2007

Biotin deficiency inhibits heme synthesis and impairs mitochondria in human lung fibroblasts.

Four of the 5 biotin-dependent carboxylases (BDC) are in the mitochondria. BDC replace intermediates in the Krebs [tricarboxylic acid (TCA)] cycle that are regularly removed for the synthesis of key metabolites such as heme or amino acids. Heme, unlike amino acids, is not recycled to regenerate these intermediates, is not utilized from the diet, and must be synthesized in situ. We studied whether biotin deficiency (BD) lowers heme synthesis and whether mitochondria would be disrupted. Biotin-deficient medium was prepared by using bovine serum stripped of biotin with charcoal/dextran or avidin. Biotin-deficient primary human lung fibroblasts (IMR90) lost their BDC and senesced before biotin-sufficient cells. BD caused heme deficiency; there was a decrease in heme content and heme synthesis, and biotin-deficient cells selectively lost mitochondrial complex IV, which contains heme-a. Loss of complex IV, which is part of the electron transport chain, triggered oxidant release and oxidative damage, hallmarks of heme deficiency. Restoring biotin to the biotin-deficient medium prevented the above changes. Old cells were more susceptible to biotin shortage than young cells. These findings highlight the biochemical connection among biotin, heme, and iron metabolism, and the mitochondria, due to the role of biotin in maintaining the biochemical integrity of the TCA cycle. The findings are discussed in relation to aging and birth defects in humans.

Biotin↗
PubMed2006

Endotoxin detection in a competitive electrochemical assay: synthesis of a suitable endotoxin conjugate.

A biotin-lipopolysaccharide (biotin-LPS) conjugate was synthesized from LPS smooth from Salmonella minnesota, yielding a conjugate with a biotin/LPS ratio equal to 1:1 and endotoxic activity of 0.08 EU ng(-1). The conjugate was used in an amperometric competitive assay to determine endotoxins with endotoxin-neutralizing protein (ENP) as the recognition element. The assay is performed on a modified electrode, involving the covalent binding of carboxymethyl dextran (CMDex) to a cystamine-modified gold electrode and then the covalent binding of the recognition protein, ENP, to CMDex. The assay is carried out by incubating the modified electrode in an LPS sample to which biotin-LPS was added. Both species compete for the recognition sites on the modified surface. After the incubation stage and a careful rinsing, the electrode is immersed in a solution containing neutravidin-horseradish peroxidase conjugate (N-HRP), which binds to the sites containing biotin-LPS on the electrode. The system is rinsed and a current signal is generated by the addition of hydrogen peroxide and a redox mediator. The assay is able to detect LPS from Salmonella minnesota at concentrations as low as 0.1 ng ml(-1), equivalent to 0.07 EU ml(-1).

Biotin↗