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M J Runswick

Publications and source records attributed to M J Runswick.

68 records · Page 4Linked to original sources
PubMed1983

The amino acid sequence of the beta-subunit of ATP synthase from bovine heart mitochondria.

The amino acid sequence of the beta-subunit of bovine heart mitochondrial ATP synthase has been determined by protein sequence analysis. The polypeptide chain of 478 amino acids is blocked at its NH2 terminal. Comparison of this sequence with sequences of the corresponding proteins from Escherichia coli (Saraste, M., Gay, N.J., Eberle, A., Runswick, M.J., and Walker, J.E. (1981) Nucleic Acids Res. 9, 5287-5296) and maize and spinach chloroplasts Krebbers, E.T., Larrinua, I. M., McIntosh, L., and Bogorad, L. (1982) Nucleic Acids Res. 10, 4985-5002; Kurawski, G., Bottomley, W., and Whitfield, P.R. (1982) Proc. Natl. Acad. Sci. U.S.A. 79, 6260-6264) shows that the protein is highly conserved. 70% of residues are identical in E. coli and beef mitochondria. This contrasts with some of the other subunits in the enzyme complex which are much less conserved.

ATP Synthetase Complexes↗
PubMed1982

Distantly related sequences in the alpha- and beta-subunits of ATP synthase, myosin, kinases and other ATP-requiring enzymes and a common nucleotide binding fold.

The alpha- and beta-subunits of membrane-bound ATP synthase complex bind ATP and ADP: beta contributes to catalytic sites, and alpha may be involved in regulation of ATP synthase activity. The sequences of beta-subunits are highly conserved in Escherichia coli and bovine mitochondria. Also alpha and beta are weakly homologous to each other throughout most of their amino acid sequences, suggesting that they have common functions in catalysis. Related sequences in both alpha and beta and in other enzymes that bind ATP or ADP in catalysis, notably myosin, phosphofructokinase, and adenylate kinase, help to identify regions contributing to an adenine nucleotide binding fold in both ATP synthase subunits.

ATP Synthetase Complexes↗
PubMed1981

The atp operon: nucleotide sequence of the genes for the gamma, beta, and epsilon subunits of Escherichia coli ATP synthase.

The nucleotide sequence of the promoter distal region of the atp (or unc) operon of Escherichia coli has been determined. It encodes the gamma, beta and epsilon subunits of the ATP-synthase complex and includes a noncoding sequence in which transcription of the operon probably terminates. This work completes the nucleotide sequence of the operon which contains nine genes: eight encode structural proteins of the ATP-synthase complex; a ninth, the first in the operon, may be a pilot for assembly. The genes for the alpha and beta subunits have evolved from a common ancestor.

ATP Synthetase Complexes↗
PubMed1980

D-glyceraldehyde-3-phosphate dehydrogenase. The purification and characterisation of the enzyme from the thermophiles Bacillus stearothermophilus and Thermus aquaticus.

1. D-Glyceraldehyde-3-phosphate dehydrogenase from two thermophilic bacteria has been purified by procedures including affinity chromatography on NAD+-Sepharose. 2. Methods for making NAD+-free enzyme are also described. 3. Both the holo and apo forms of the enzyme from Bacillus stearothermophilus have been crystallised. 4. The enzymes are tetrameric and composed of four chemically identical polypeptide chains of molecular weight 36,000. 5. The enzymes are much more stable to heat than their counterparts from mesophiles.

Chromatography, Affinity↗
PubMed1980

D-glyceraldehyde-3-phosphate dehydrogenase. Complete amino-acid sequence of the enzyme from Bacillus stearothermophilus.

1. The complete amino acid sequence of D-glyceraldehyde-3-phosphate dehydrogenase from the moderate thermophile Bacillus stearothermophilus has been determined. 2. This has been achieved largely by the automated sequence analysis of large fragements derived by chemical cleavage with cyanogen bromide, BNPS-skatole [the product of reaction between N-bromosuccinimide and 2-(nitrophenyl-sulphenyl)-3-methylindole] and hydroxylamine and enzymic hydrolysis with trypsin at arginine residues. 3. The sequence is as follows: (See Text). It has been numbered to maximise homology with the four complete sequences of this enzyme from other sources. Hence the N-terminal residue is numberd 0 and two deletions and two insertions have been introduced. 4. The inability of the B. stearothermophilus apo-enzyme to transfer an acyl moiety from Cys-149 to Lys-183 oberved with muscle enzymes is explained by the replacement of lysine by arginine in the enzyme from the thermophilic organism. 5. The sequences of the S-loop regions, which form the core of the tetrameric enzyme, are similar to each other in B. stearothermophilus and Thermus aquaticus and differ from the highly conserved S-loops of three enzymes from mesophiles.

Amino Acid Sequence↗
PubMed1979

Identification of the amino acid residue modified in Bacillus stearothermophilus alcohol dehydrogenase by the NAD+ analogue 4-(3-bromoacetylpyridinio)butyldiphosphoadenosine.

4-(3-Bromoacetylpyridinio)butyldiphosphoadenosine was synthesized with a [carbonyl-14C]acetyl label. The reactive coenzyme analogue inactivates alcohol dehydrogenase from Bacillus stearothermophilus by forming a covalent enzyme-coenzyme compound. The inactivation kinetics as well as the spectral properties of the modified enzyme after treatment with sodium hyposulphite suggest that the analogue is bound at the coenzyme binding site. B. stearothermophilus alcohol dehydrogenase modified with 14C-labelled coenzyme analogue and subseqeuntly carboxymethylated with unlabelled iodoacetic acid was digested with trypsin. The radioactive peptide was isolated and sequenced in parallel with the corresponding peptide similarly isolated from unmodified enzyme that had instead been carboxymethylated with iodo[14C]acetic acid. Amino acid and sequence analysis show that Cys-38 of the B. stearothermophilus alcohol dehydrogenase was modified by the reactive coenzyme analogue. This residue is homologous to Cys-43 in yeast alcohol dehydrogenase and Cys-46 in the horse liver enzyme but, unlike the latter two, Cys-38 is not reactive towards iodoacetate in the native bacterial enzyme.

Adenosine Diphosphate↗
PubMed1979

Minigastrin; corrected structure and synthesis.

Evidence is presented that minigastrin is the C-terminal tetradecapeptide amide of gastrin and not the tridecapeptide amide as previously reported. Synthesis of the tetradecapeptide amide sequence, Trp-Leu-[Glu]5-Ala-Tyr-Gly-Trp-Met-Asp-Phe-Nh2, was achieved by a series of fragment couplings which were mediated by the dicyclohexylcarbodiimide procedure in presence of either N-hydroxysuccinimide or 1-hydroxybenzotriazole. Purification of all intermediate fragments, and of the final protected tetradecapeptide amide, was by Sephadex LH-20 chromatography. Removal of the protecting groups was effected by treatment with 90% trifluoroacetic acid in the presence of a large excess of scavengers. Purification by ion-exchange chromatography afforded the pure tetradecapeptide amide. This material had full physiological activity.

Amino Acid Sequence↗
PubMed1976

The subunits of rabbit-muscle phosphofructokinase. A search for sequence repetition.

Rabbit muscle phosphofructokinase uniformly carboxymethylated with iodo[2-14C]acetate consists of subunits with a molecular weight of 80 000 +/- 5000. The subunit polypeptide chain contains 16 and 52 residues respectively of cysteine and arginine and, contrary to previous results, peptide mapping experiments gave no indication that phosphofructokinase chains yield fewer than the expected numbers of cysteine and arginine containing peptides. To test further for the possible occurrence of repeat sequences within a single subunit chain, cysteine-containing peptides were isolated and sequenced from tryptic and thermolytic digests of s-[2-14C]carboxymethylated phosphofructokinase. In all, 15 different cysteine sequences (comprising a total of 104 residues) were identified, showing that not more than one of an expected 16 cysteine-containing sequences is repeated, and that the subunits of phosphofructokinase are of unique sequence along their entire length. The near quantitative isolation of several cysteine-containing peptides shows further that all subunits are of similar if not identical sequence.

Amino Acid Sequence↗