Biochemical characterization of a psychrophilic and halotolerant α-carbonic anhydrase from a deep-sea bacterium, .

Prokaryotic α-carbonic anhydrases (α-CA) are metalloenzymes that catalyze the reversible hydration of CO to bicarbonate and proton. We had reported the first crystal structure of a pyschrohalophilic α-CA from a deep-sea bacterium, SS9. In this manuscript, we report the first biochemical characterization of α-CA (PprCA) which revealed several catalytic properties that are atypical for this class of CA's.

A High-Resolution Crystal Structure of a Psychrohalophilic α-Carbonic Anhydrase from Photobacterium profundum Reveals a Unique Dimer Interface.

Bacterial α-carbonic anhydrases (α-CA) are zinc containing metalloenzymes that catalyze the rapid interconversion of CO2 to bicarbonate and a proton. We report the first crystal structure of a pyschrohalophilic α-CA from a deep-sea bacterium, Photobacterium profundum. Size exclusion chromatography of the purified P.

Rhodococcus jostii porin A (RjpA) functions in cholate uptake.

RjpA in Rhodococcus jostii is the ortholog of a channel-forming porin, MspA. Deletion of rjpA delayed growth of R. jostii on cholate but not on cholesterol.

Protein glycosylation in Helicobacter pylori: beyond the flagellins?

Glycosylation of flagellins by pseudaminic acid is required for virulence in Helicobacter pylori. We demonstrate that, in H. pylori, glycosylation extends to proteins other than flagellins and to sugars other than pseudaminic acid.

Cj1121c, a novel UDP-4-keto-6-deoxy-GlcNAc C-4 aminotransferase essential for protein glycosylation and virulence in Campylobacter jejuni.

Campylobacter jejuni produces glycoproteins that are essential for virulence. These glycoproteins carry diacetamidobacillosamine (DAB), a sugar that is not found in humans. Hence, the enzymes responsible for DAB synthesis represent potential therapeutic targets.

RpoS-regulated genes of Escherichia coli identified by random lacZ fusion mutagenesis.

RpoS is a conserved alternative sigma factor that regulates the expression of many stress response genes in Escherichia coli. The RpoS regulon is large but has not yet been completely characterized. In this study, we report the identification of over 100 RpoS-dependent fusions in a genetic screen based on the differential expression of an operon-lacZ fusion bank in rpoS mutant and wild-type backgrounds.