Molecular genetic approaches to the study of E. coli flavoproteins

Guest, J. R.; Rice, David W.

doi:10.1515/9783111521350-020

Cited by 7 publications

(4 citation statements)

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“…The anchor proteins of these enzymes show little sequence similarity despite the fact that the Fp and Ip proteins are very similar in sequence (Philips etat., 1987). The hydropathy profiles of E. coli SDHC+SDHD (Wood et ai, 1984) and FRDC + FRDD (Grundstrom and Jaurin, 1982) are similar with up to three possible transmembrane segments in each polypeptide (Guest and Rice, 1984). B. subtilis cytti558 and W. succinogenes cytbfrd also have similar hydropathy profiles with five possible transmembrane segments ( Fig.…”

Section: Identification Of Axial Haem Iigandsmentioning

confidence: 86%

Role of His residues in Bacillus subtilis cytochrome b558 for haem binding and assembly of succinate: quinone oxidoreductase (complex II)

Fridén

Hederstedt

1990

Molecular Microbiology

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Cytochrome b558 in the cytoplasmic membrane of Bacillus subtilis constitutes the anchor and electron acceptor to the flavoprotein (Fp) and iron-sulphur protein (Ip) in succinate:quinone oxidoreductase, and seemingly contains two haem groups. EPR and MCD spectroscopic data indicate bis-imidazole ligation of the haem. Apo-cytochrome was found in the membrane fraction of haem-deficient B. subtilis, suggesting that during biogenesis of the oxidoreductase the cytochrome b558 polypeptide is embedded into the membrane prior to the incorporation of haem and subsequent binding of Fp and Ip. The six His residues in cytochrome b558 were individually changed to Tyr to attempt identification of residues serving as haem axial ligands and to analyse the role of His residues for assembly and function of the oxidoreductase. From the properties of the mutants, His-47 can be excluded as a haem ligand. The remaining His residues (at positions 13, 28, 70, 113 and 155) are located in or close to four predicted transmembrane segments. The Tyr-28 and Tyr-70 mutant proteins appeared to lack one of the two haems. Only the Tyr-13 and Tyr-47 mutant cytochromes were found to function as anchors for Fp and Ip, but the Tyr-13 mutant cytochrome assembles into an enzymatically defective succinate:quinone oxidoreductase. It is concluded from a combination of the experimental findings, sequence comparisons and membrane topology data that His-28, His-70 and His-155 are probably haem axial ligands in a dihaem cytochrome b558. His-70 and His-155 may be ligands to the same haem.

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Section: Identification Of Axial Haem Iigandsmentioning

confidence: 86%

Role of His residues in Bacillus subtilis cytochrome b558 for haem binding and assembly of succinate: quinone oxidoreductase (complex II)

Fridén

Hederstedt

1990

Molecular Microbiology

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“…Extensive genetic analysis in Escherichia coli (Guest & Rice, 1984;Spencer & Guest, 1985) has shown that the E and F genes of the ace operon encode the El and E2 components of the pyruvate dehydrogenase complex, and the A and B genes of the suc operon encode the El and E2 components of the 2-oxoglutarate dehydrogenase complex respectively. In contrast, lipoamide dehydrogenase is coded for by a single gene, lpd, which is linked to the ace operon but which can operate under the control of its own promoter.…”

Section: Introductionmentioning

confidence: 99%

Cloning and Characterization of the Gene Encoding Lipoamide Dehydrogenase in Saccharomyces Cerevisiae

Roy

Dawes²

1987

Microbiology

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The LPD1 gene of S. cerevisiae, which encodes lipoamide dehydrogenase (EC 1.8.1.4), has been cloned and characterized. The LPD1 gene is present as a single copy in the yeast genome and is transcribed to give a polyadenylated mRNA species of approximately 2.0 kb. The synthesis of lipoamide dehydrogenase in yeast is subject to carbon catabolite repression since both the level of the LPD1 transcript and the accumulation of the lipoamide dehydrogenase subunit polypeptide were greatly reduced in wild-type cells grown on glucose compared to those grown on a variety of non-fermentable carbon sources. Strains defective in LPD1 but transformed with the LPD1 gene on a high copy number vector exhibited elevated levels of the LPD1 transcript as well as increased lipoamide dehydrogenase activity when grown on glycerol. Immunoblotting experiments confirmed that such transformants over-expressed lipoamide dehydrogenase protein. Transcription from the LPD1 sequence on plasmid pGP1 still appeared to be subject to some catabolite repression despite the presence of multiple copies of the plasmid in the cell.

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“…In fact, there is a remarkable degree of sequence homology along the entire length of the polypeptide chains of the E. coli lipoamide dehydrogenase and other sequenced disulphide oxidoreductases human erythrocyte glutathione reductase (Krauth-Siege1 et al, 1982) and Tn901-encoded mercuric reductase (Brown et al, 1983). It is also possible to align tryptic peptides from the pig heart lipoamide dehydrogenase according to their homologies with existing sequences (Arscott et al, 1982;Stephens et al, 1983).…”

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confidence: 99%

Cloning and sequence analysis of the pyruvate and 2-oxoglutarate dehydrogenase complex genes of Escherichia coli

Guest

Darlison

Spencer

et al. 1984

Biochemical Society Transactions

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The pyruvate and 2-oxoglutarate dehydrogenase complexes catalyse the oxidative decarboxylation of pyruvate or 2-Abbreviations used: kb, kilobases; SDS, sodium dodecyl sulphate. oxoglutarate and in Escherichia coli they contain multiple copies of three types of enzymic component: the pyruvate or 2-oxoglutarate dehydrogenase (Elp or Elo), a specific dihydrolipoamide acyltransferase (E2p or E20), and a common lipoamide dehydrogenase (E3). The El and E3 components assemble around cores of 24 E2 chains and produce large complexes (M, = 2 4 x lo6) with disproportionate polypeptide stoichiometries in the range 0.

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Molecular genetic approaches to the study of E. coli flavoproteins

Cited by 7 publications

References 0 publications

Role of His residues in Bacillus subtilis cytochrome b558 for haem binding and assembly of succinate: quinone oxidoreductase (complex II)

Role of His residues in Bacillus subtilis cytochrome b558 for haem binding and assembly of succinate: quinone oxidoreductase (complex II)

Cloning and Characterization of the Gene Encoding Lipoamide Dehydrogenase in Saccharomyces Cerevisiae

Cloning and sequence analysis of the pyruvate and 2-oxoglutarate dehydrogenase complex genes of Escherichia coli

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