ABSTRACT
Previous evidence has shown that the M1 and L pyruvate kinase isozymes differ markedly in kinetic and immunological properties, amino acid compositions and peptide maps. However, the amino acid sequence results we present here for the N-terminal region and for a region of the C domain show that the M1 and L isozymes are very similar. The variable length of the N-terminal sequences also explains the difference in regulation by phosphorylation between the M1 and L isozymes. The M1 isozyme lacks the serine residue that has been shown to be phosphorylated in the L isozyme.
Subject(s)
Isoenzymes/analysis , Liver/enzymology , Muscles/enzymology , Pyruvate Kinase/analysis , Amino Acid Sequence , Amino Acids/analysis , Animals , Cats , Crystallography , Kinetics , Macromolecular Substances , RatsABSTRACT
Fructose-1,6-bisphosphate aldolase was purified from human skeletal-muscle by affinity elution chromatography. Four CNBr-cleavage fragments were purified by gel filtration, and their N-terminal amino acid sequences were determined. Cleavage with o-iodosobenzoic acid at the three tryptophan residues also yielded fragments suitable for N-terminal sequence analysis. Thus, the sequence of 272 of the 363 residues was established. These sequence results allow many of the discrepancies between the two published rabbit skeletal-muscle aldolase sequences to be resolved. The human aldolase sequence reported here is 96% identical to a "consensus" rabbit aldolase sequence. A comparison with a partial sequence of Drosophila aldolase (103 residues) shows 80% identity. The determination of the amino acid sequence of human aldolase is important for the interpretation of the crystal structure of this enzyme.
Subject(s)
Cyanogen Bromide , Fructose-Bisphosphate Aldolase/isolation & purification , Iodobenzoates , Muscles/enzymology , Peptide Fragments/isolation & purification , Amino Acid Sequence , Animals , Drosophila/enzymology , Humans , RabbitsABSTRACT
Pyruvate kinase was purified from cat and trout muscle. The enzymes had similar amino acid compositions and subunit molecular weights. In contrast to the mammalian enzyme, the trout muscle pyruvate kinase was activated by fructose 1,6-bisphosphate. However, unlike the L-type pyruvate kinase from mammalian liver it was not phosphorylated by cyclic-AMP-dependent protein kinase. The purified enzyme from cat muscle was carboxymethylated with iodo[2-14C]acetic acid under conditions that led to the preferential labelling of one especially reactive thiol group. The labelled enzyme was cleaved with CNBr, and the radioactive fragment purified. Amino acid sequence analysis of the reactive-thiol-containing fragment from cat muscle pyruvate kinase showed it had the following sequence: Ile-Gly-Arg-[14C]CmCys-Asn-Arg-Ala-Gly-Lys-Pro-Val-Ile-CmCys-Ala-Thr-Gln- Hse. The corresponding peptide from trout pyruvate kinase had only one difference in its amino acid composition and the sequence around the reactive thiol was identical.
Subject(s)
Muscles/enzymology , Pyruvate Kinase/isolation & purification , Amino Acids/isolation & purification , Animals , Cats , Chemical Phenomena , Chemistry , Molecular Weight , Species Specificity , Structure-Activity Relationship , Sulfhydryl Compounds/analysis , TroutABSTRACT
The complete amino acid sequence of yeast phosphoglycerate kinase, comprising 415 residues, was determined. The sequence of residues 1-173 was deduced mainly from nucleotide sequence analysis of a series of overlapping fragments derived from the relevant portion of a 2.95-kilobase endonuclease-HindIII-digest fragment containing the yeast phosphoglycerate kinase gene. The sequence of residues 174-415 was deduced mainly from amino acid sequence analysis of three CNBr-cleavage fragments, and from peptides derived from these fragments after digestion by a number of proteolytic enzymes. Cleavage at the two tryptophan residues with o-iodosobenzoic acid was also used to isolate fragments suitable for amino acid sequence analysis. Determination of the complete sequence now allows a detailed interpretation of the existing high-resolution X-ray-crystallographic structure. The sequence -Ile-Ile-Gly-Gly-Gly- occurs twice in distant parts of the linear sequence (residues 232-236 and 367-371). Both these regions contribute to the nucleoside phosphate-binding site. A comparison of the sequence of yeast phosphoglycerate kinase reported here with the sequences of phosphoglycerate kinase from horse muscle and human erythrocytes shows that the yeast enzyme is 64% identical with the mammalian enzymes. The yeast has strikingly fewer methionine, cysteine and tryptophan residues.
Subject(s)
Phosphoglycerate Kinase , Amino Acid Sequence , Animals , Base Sequence , Chemical Phenomena , Chemistry , Chromatography, Gel , DNA, Fungal , Deoxyribonucleotides/analysis , Genes , Horses , Humans , Peptide Fragments/analysis , Phosphoglycerate Kinase/genetics , Saccharomyces cerevisiae/enzymologyABSTRACT
The complete amino acid sequence of human erythrocyte diphosphoglycerate mutase, comprising 239 residues, was determined. The sequence was deduced from the four cyanogen bromide fragments, and from the peptides derived from these fragments after digestion with a number of proteolytic enzymes. Comparison of this sequence with that of the yeast glycolytic enzyme, phosphoglycerate mutase, shows that these enzymes are 47% identical. Most, but not all, of the residues implicated as being important for the activity of the glycolytic mutase are conserved in the erythrocyte diphosphoglycerate mutase.
Subject(s)
Bisphosphoglycerate Mutase/blood , Erythrocytes/enzymology , Phosphotransferases/blood , Amino Acid Sequence , Binding Sites , Biological Evolution , Cyanogen Bromide , Humans , Peptide Fragments/isolation & purification , Phosphoglycerate Mutase , Saccharomyces cerevisiae/enzymologyABSTRACT
The position of the yeast phosphoglycerate kinase (PGK) gene has been mapped on a 2.95kb Hind III fragment. We have determined the nucleotide sequence of the 5' flanking region and compared this sequence with those from 16 other yeast genes. PGK, like all other yeast genes has an adenine residue at position -3. It has two possible TATA boxes at positions -114 and -152 and a CAAT box at -129. In addition we have defined a structure at position -63 to -39 that is common to all yeast genes that encode an abundant RNA. This structure is a CT-rich block followed, about 10 nucleotides later, by the sequence CAAG.
Subject(s)
DNA, Fungal/genetics , Operon , Phosphoglycerate Kinase/genetics , Saccharomyces cerevisiae/enzymology , Amino Acid Sequence , Base Sequence , DNA Restriction Enzymes , Genes , Nucleic Acid Hybridization , Saccharomyces cerevisiae/genetics , Species Specificity , Transcription, GeneticABSTRACT
The complete amino acid sequence of yeast phosphoglycerate mutase comprising 241 residues has been determined. The sequence was deduced from the two cyanogen bromide fragments, and from the peptides derived from these fragments after digestion by a number of proteolytic enzymes. Determination of this sequence now allows a detailed interpretation of the existing high-resolution X-ray crystallographic structure. A comparison of the sequence reported here with the sequences of peptides from phosphoglycerate mutases from other species, and with the sequence of erythrocyte diphosphoglycerate mutase, indicates that these enzymes have a high degree of structural homology. Autolysis of phosphoglycerate mutase by yeast extracts leads to the complete loss of mutase activity, and the formation of electrophoretically distinguishable forms (R. Sasaki, E. Sugimoto & H. Chiba, Archs Biochem. Biophys. 115, 53-61 (1966)). It is apparent from the amino acid sequence that these changes are due to the loss of an 8-12 residue peptide from the C-terminus.
Subject(s)
Phosphoglycerate Mutase , Phosphotransferases , Amino Acid Sequence , Peptide Fragments , Saccharomyces cerevisiaeABSTRACT
The structure of yeast phosphoglycerate kinase has been determined with data obtained from amino acid sequence, nucleotide sequence, and X-ray crystallographic studies. The substrate binding sites, as deduced from electron density maps, are compatible with known substrate specificity and the stereochemical requirements for the enzymic reaction. A carboxyl-imidazole interaction appears to be involved in controlling the transition between the open and closed forms of the enzyme.
Subject(s)
Phosphoglycerate Kinase , Saccharomyces cerevisiae/enzymology , Amino Acid Sequence , Models, Molecular , Phosphoglycerate Kinase/isolation & purification , Phosphoglycerate Kinase/metabolism , Protein Conformation , Substrate Specificity , X-Ray DiffractionABSTRACT
The structure of yeast phosphoglycerate mutase determined by X-ray crystallographic and amino acid sequence studies has been interpreted in terms of the chemical, kinetic and mechanistic observations made on this enzyme. There are two histidine residues at the active site, with imidazole groups almost parallel to each other and approximately 0.4 nm apart, positioned close to the 2 and 3 positions of the substrate. The simplest interpretation of the available information suggests that a ping-pong type mechanism operates in which at least one of these histidine residues participates in the phosphoryl transfer reaction. The flexible C-terminal region also plays an important role in the enzymic reaction.
Subject(s)
Phosphoglycerate Mutase/metabolism , Phosphotransferases/metabolism , Amino Acid Sequence , Animals , Binding Sites , Catalysis , Chemical Phenomena , Chemistry , Kinetics , Macromolecular Substances , Models, Biological , Models, Molecular , X-Ray DiffractionABSTRACT
The complete amino acid sequence of hen ovalbumin, comprising 385 residues, has been determined. The sequence was deduced from the 17 cyanogen bromide fragments and from peptides derived by digestion with a number of proteolytic enzymes. The molecular weight of the polypeptide chain of ovalbumin is 42699. Ovalbumin has four sites of postsynthetic modification; in addition to the acetylated N terminus, the carbohydrate moiety is located at Asn-292, and the two phosphorylated serines are at residues 68 and 344. The 'signal sequence' of ovalbumin is between residues 234 and 252. The heptapeptide released during the conversion of ovalbumin to plakalbumin by subtilisin digestion corresponds to residues 346-352. The hen ovalbumin polymorphism characterised by an Asn leads to Asp replacement results from a mutation at residue 311. The amino acid sequence of ovalbumin deduced from these amino acid sequence studies is in complete agreement with the sequence of mRNA determined by McReynolds et al. [Nature (Lond.) 273, 723-728 (1978)].
Subject(s)
Ovalbumin , Amino Acid Sequence , Animals , Chickens , Egg White , Endopeptidases , Female , Peptide Fragments/analysis , Peptide HydrolasesABSTRACT
Phosphoserine peptides have been isolated by a diagonal electrophoresis method from proteolytic digests of ovalbumins from hen, grouse, turkey, golden pheasant, magpie goose, chinese goose, Aylesbury duck and fulvous whistling duck. The amino acid sequences of these peptides have been determined. There are two sites of phosphorylation in each ovalbumin, which are located in two different regions of the ovalbumin molecule. Amino acid replacements are more frequent in the site 1 sequences than in the site 2 sequences. Both site 1 and site 2 sequences contain invariant residues. Sequence variations occur near the serine residues that are phosphorylated, but the amino acid two residues C-terminal to the phosphoserine is always glutamic acid, suggesting that this may be a recognition signal for the phosphorylating enzyme. Variations in amino acid sequence among the species are consistent with differences in the ovalbumins determined by peptide mapping and quantitative immunoprecipitation assays. A phylogenetic tree has been constructed from a comparison of the sequences of 248 residues from the eight ovalbumins.