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An extended bioinformatic analysis has described the genome-based link for the absence of GHS biosynthesis, the presence of the type III pantothenate kinase (PanK) and the presence of the coenzyme A-disulfide reductase (CoADR)-like enzymes in a number of bacteria and spirochetes. The results have indicated that the type III PanK in the spore-forming Bacillus anthracis plays a vital role in the novel thiol/disulfide redox biology of this category A biodefense pathogen.

Research has been conducted on the heme-deficient gram-positive bacterium Streptococcus pyogenes. The analysis of the gene products that are important in the aerobic metabolism is presented.

This review documents the applications of cysteine-sulfenic acid (Cys-SOH) derivative introduction into diverse proteins and its impact on proteins' function and stabilization. The role of Cys-SOH in various cellular processes and in the industrial production of chemicals is also discussed.

A study was conducted to characterize the Enterococcus faecalis Nox C42S mutant. An Applied Photophysics DX.17MV stopped-flow spectrophotometer was used to carry out rapid-reaction analyses. Dissolved oxygen solutions for stopped-flow work were determined by bubbling buffer in glass syringes. Results confirmed a C(4a)-peroxyflavin intermediate in the oxygen reaction of the mutant. Findings also showed that the replacement of Cys42 with Ser leads to an altered O2 reduction stoichiometry.

The crystal structure characterization at 2.10 [Angstrome] resolution for the Bacillus anthracis coenzyme A-disulfide reductase isoform (BaCoADR-RHD) containing a C-terminal rhodanese homology domain (RHD) which is the first structural representative of the multidomain proteins class of the rhodanese superfamily is reported. The results indicated that the BaCoADR-RHD isoform does not catalyze the reduction of coenzyme A-disulfide, but both enzymes conserved the Cys-SSCoA redox center.

The kinetic, redox properties and 2.30 Angstrom resolution structural characterization of Bacillus anthracis coenzyme A-disulfide reductase (CoADR, BACoADR) is described. The results from the NAD(P)H-reduced BACoADR structures provide insight into the reduced form of Cys42-SH/CoASH) of the Cys42-SSCoA redox center.

The structural and functional divergence between [alpha]-glycerophosphate oxidase (GlpO) from Streptococcus sp. and the bacterial and mitochondrial [alpha]-glycerophosphate dehydrogenases (GlpDs) is demonstrated.

The multiwavelength anomalous dispersion data was used to solve the crystal structure of Staphylococcus aureus coenzyme A-disulfide reductase (CoADR) and refine it at a resolution of 1.54 Angstrom. The bioinformatics analyses indicate that CoADR enzymes are broadly distributed in both bacterial and archaeal kingdoms, suggesting an even broader significance for the CoASH/CoAS-disulfide redox system in prokaryotic thiol/disulfide homeostasis.

Evidence showing that the active, wild-type oxidase exhibits thermodynamic inequivalence between the two active sites per dimer has been provided. The use of NADPH for the generation of the wild-type enzyme EH2'/EH4 showed differential behavior during NAD+ titration as only a single FADH2 per dimer binds tightly to NAD+ to give the charge-transfer complex. A second FADH2, however, transfers its electrons to the lone Cys42-sulfenic acid redox center that remains oxidized during reductive titration.

The alkanesulfonate FMN reductase (SsuE) from Escherichia coli catalyzes the reduction of FMN by NADPH to provide reduced flavin for the monooxygenase (SsuD) enzyme. The vapor-diffusion technique yielded single crystals that grow as hexagonal rods and diffract to 2.9 A resolution using synchrotron X-ray radiation. The protein crystallizes in the primitive hexagonal space group P622. The SsuE protein lacks any cysteine or methionine residues owing to the role of the SsuE enzyme in the acquisition of sulfur during sulfate starvation. Therefore, substitution of two leucine residues (Leu114 and Leu165) to methionine was performed to obtain selenomethionine-containing SsuE for MAD phasing. The selenomethionine derivative of SsuE has been expressed and purified and crystals of the protein have been obtained with and without bound FMN. These preliminary studies should lead to the structure solution of SsuE. It is anticipated that this new protein structure will provide detailed structural information on specific active-site regions of the protein and insight into the mechanism of flavin reduction and transfer of reduced flavin.