Disease relevance of bioB

• Crossfeeding studies with Escherichia coli bio mutants indicated that the insertion is in the bioB gene [1].
• The amount of leftward transcription in the Escherichia coli bio operon, as measured by hybridization and by beta-galactosidase assays in lac-bio fusion strains, was determined in bacteria lysogenic for lambda bio phage carrying different amounts of DNA corresponding to rightward message, and in bacteria with polar or nonpolar bioB mutations [2].
• Isolation of a Rhodobacter capsulatus bioB mutant and cloning of the bioB gene [1].
• Analysis of the biotin biosynthesis pathway in coryneform bacteria: cloning and sequencing of the bioB gene from Brevibacterium flavum [3].
• The contribution of cysteine desulfurase, the NifS protein of Klebsiella pneumoniae and the IscS protein of Escherichia coli, to the biotin synthase reaction was investigated in in vitro and in vivo reaction systems with E. coli [4].

High impact information on bioB

• Its amino acid sequence shares the CysXXX-CysXXCys sequence with MiaB from E. coli as well as with biotin synthase and lipoate synthase [5].
• Biotin synthase is required for the conversion of dethiobiotin to biotin and requires a number of accessory proteins and small molecule cofactors for activity in vitro [6].
• Such a sequence is also present in the activase of the pyruvate formate-lyase and in the biotin synthase, both carrying an iron-sulfur center involved in reductive activation of S-adenosylmethionine [7].
• A cell-free extract from an Escherichia coli strain containing a cloned bioB (biotin synthase) gene was incubated with [14C]dethiobiotin, which was converted to [14C] biotin [8].
• Biotin synthase (BioB) converts dethiobiotin into biotin by inserting a sulfur atom between C6 and C9 of dethiobiotin in an S-adenosylmethionine (SAM)-dependent reaction [9].

Chemical compound and disease context of bioB

• Biotin synthase catalyzes the chemically difficult final step in the biotin biosynthetic pathway and is encoded by the bioB gene in Escherichia coli [10].
• We have reported [Ifuku, O., Kishimoto, J., Haze, S., Yanagi, M. & Fukushima, S. (1992) Biosci. Biotechnol. Biochem. 56, 1780-1785] the enzymic conversion of dethiobiotin to biotin (catalyzed by the enzyme encoded by bioB) in cell-free extract of Escherichia coli which had been genetically engineered for high bioB expression [11].
• [2Fe-2S] to [4Fe-4S] cluster conversion in Escherichia coli biotin synthase [12].
• Role of the [2Fe-2S] cluster in recombinant Escherichia coli biotin synthase [9].
• Further investigation on the turnover of Escherichia coli biotin synthase with dethiobiotin and 9-mercaptodethiobiotin as substrates [13].

Biological context of bioB

• The changes at position -15 (with respect to the center of the inverted repeat) cause constitutivity of leftward operon expression and decreased expression of bioB, due to alteration of the -35 region of the rightward promoter [14].
• A cosmid that complements the bioB insertion was isolated, and the bioB gene was localized to a 2.85-kilobase EcoRI-PstI fragment [1].
• From the nucleotide sequence of the promoter proximal region of the bioB gene, a 13-oligonucleotide sequence believed to be the early transcription termination site has been located [15].
• Its deduced amino acid sequence is 35.7% and 31.5% identical to that of the E. coli and Bacillus sphaericus bioB gene products, respectively [3].
• Nucleotide sequence analysis of this fragment revealed that the bioB gene of B. flavum consists of a 1005 bp open reading frame [3].

Anatomical context of bioB

• Moreover, the IscS protein of E. coli stimulated the biotin synthase reaction in the presence of L-cysteine in the cell-free system [4].

Associations of bioB with chemical compounds

• B. flavum mutants obtained by in vivo disruption of the bioB gene lost their ability to grow on minimal medium containing dethiobiotin, indicating that the bioB gene product is necessary for the conversion of dethiobiotin to biotin [3].
• Biochemical and molecular characterization of the biotin biosynthetic pathway in plants has dealt primarily with biotin synthase [16].
• Biotin synthase is an iron-sulfur protein that utilizes AdoMet to catalyze the presumed radical-mediated insertion of a sulfur atom between the saturated C6 and C9 carbons of dethiobiotin [17].
• Here we report Mössbauer studies of (57)Fe-reconstituted biotin synthase showing that anaerobically prepared enzyme can accommodate two (4Fe-4S) clusters per dimer [18].
• Iron-sulfur center of biotin synthase and lipoate synthase [18].

Analytical, diagnostic and therapeutic context of bioB

• The positions of the bioB endpoints in relation to the pB promoter were determined by electron microscopy of heteroduplexes [2].
• The cofactor content of in vivo, as-isolated, and reconstituted forms of recombinant Escherichia coli biotin synthase (BioB) has been investigated using the combination of UV-visible absorption, resonance Raman, and Mössbauer spectroscopies along with parallel analytical and activity assays [19].
• Biotin synthase from Escherichia coli was analyzed by nanoflow electrospray ionization mass spectrometry [20].
• The type and properties of the Fe-S cluster in recombinant Escherichia coli biotin synthase have been investigated in as-prepared and dithionite-reduced samples using the combination of UV-visible absorption and variable-temperature magnetic circular dichroism (VTMCD), EPR, and resonance Raman spectroscopies [12].
• The nature and properties of the iron-sulphur (Fe-S) cluster in as-prepared and reduced biotin synthase of Escherichia coli have been investigated by Mössbauer spectroscopy [21].

References