Cloning and nucleotide sequence of the pst A gene of Wolinella succinogenes polysulphide reductase

Abstract

The polysulphide reductase (formerly sulphur reductase) of Wolinella succinogenes is a component of the phosphorylative electron transport system with polysulphid as the terminal acceptor. Using an antiserum raised against the major subunit (PsrA, 85 kDa) of the enzyme, the corresponding gene (psr A) was cloned from a λ‐gene bank. The N‐terminal amino acid sequence of PsrA mapped within the psr A gene product, which also contained an apparent signal peptide. Downstream of the Psr A gene two more open reading frames (psrB and psrC) were found. the three genes may form a transcriptional unit with the transcription start site in front of psr A. The three genes were present only once on the genome. PsrA is a hydrophilic protein homologous to the largest subunits of six prokaryotic molybdoenzymes. PsrB is predicted to be hydrophilic, to contain ferredoxin‐like cysteine clusters and to be homologous to the smaller hydrophilic subunits of four molybdoenzymes. PsrC is predicted to be a hydrophobic protein that could possibly serve as the membrane anchor of the enzyme.

Characterization of the paramagnetic iron‐containing redox centres of Thiosphaera pantotropha periplasmic nitrate reductase

“…4b). While such a cluster has previously been suggested from sequence analysis in some cases [7,[27][28][29]31,36] biochemical evidence for such a cluster is limited to the fmding of 34 atoms of non-haem iron in FdhF [38] and the possible association of iron sulphur clusters with NarG and DmsA after fragmentation of the enzyme complexes of which they are components [40,41]. An iron-sulphur cluster(s) is clearly present in three prokaryotic assimilatory nitrate reductases [424I] which are expected to be structurally related to those of known sequence [25,26] (Fig.…”

Protein Crystallography Reveals a Role for the FS0 Cluster of Escherichia coli Nitrate Reductase A (NarGHI) in Enzyme Maturation

“…tase (PsrABC (7,8)), Salmonella typhymurium thiosulfate reductase (PhsABC (9)), and Salmonella enterica tetrathionate reductase (TtrABC (10)). These enzymes and their close relatives contribute significantly to the remarkable metabolic diversity of bacteria.…”

Purification and properties of an extremely thermostable membrane‐bound sulfur‐reducing complex from the hyperthermophilic Pyrodictium abyssi

“…Reduction of S°or polysulfides is mediated by a membrane-bound polysulfide reductase, a molybdo-enzyme branches of the universal phylogenetic tree represent hyperthermophiles (Stetter, 1992). Most of them belong to the archaeal consisting of three subunits (Krafft et al, 1992). The mechanism of electron transport from the formate dehydrogenase and hydrodomain (Woese et al, 1990).…”

“…Protein concentration was determined by the bicinchoniMolecular properties. The apparent molecular mass of the puri-nic acid solution method of Smith et al (1985), using bovine serum fied sulfur reductase complex was estimated to be 520Ϯ 20 kDa albumin as standard. The insert shows the sodium-dithionite-reduced miby gel filtration on a calibrated Superdex 200 column.…”

“…Protein was activity of 2.08 U/mg. Enzyme activity was solubilized from membranes by incubation with 1 % Triton X-100 under gentle determined routinely by the bicinchoninic acid solution method of Smith et al (1985), using bovine serum albumin as standard. stirring for 15 h at room temperature.…”