Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:4.1.2.13 (aldolase)
 3,461 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. Amino acid sequences covering the region between residues 173 and 248 [adopting the numbering system proposed by Lai, Nakai & Chang (1974) Science 183, 1204-1206] were derived for trout (Salmo trutta) muscle aldolase and for ox liver aldolase. A comparable sequence was derived for residues 180-248 of sturgeon (Acipenser transmontanus) muscle aldolase. The close homology with the rabbit muscle enzyme was used to align the peptides of the other aldolases from which the sequences were derived. The results also allowed a partial sequence for the N-terminal 39 residues for the ox liver enzyme to be deduced. 2. In the light of the strong homology evinced for these enzymes, a re-investigation of the amino acid sequence of rabbit muscle aldolase between residues 181 and 185 was undertaken. This indicated the presence of a hitherto unsuspected -Ile-Val-sequence between residues 181 and 182 and the need to invert the sequence -Glu-Val- to -Val-Glx- at positions 184 and 185. 3. Comparison of the available amino acid sequences of these enzymes suggested an early evolutionary divergence of the genes for muscle and liver aldolases. It was also consistent with other evidence that the central region of the primary structure of these enzymes (which includes the active-site lysine-227) forms part of a conserved folding domain in the protein subunit. 4. Detailed evidence for the amino acid sequences proposed has been deposited as Suy Lending Division, Boston Spa, Wetherby, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1978) 169, 5.
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PMID:Extended amino acid sequences around the active-site lysine residue of class-I fructose 1,6-bisphosphate aldolases from rabbit muscle, sturgeon muscle, trout muscle and ox liver. 53 4

Pyridoxal 5'-phosphate (PLP) in aqueous solutions can form a Schiff base complex with 14 and 16 lysine residues of rabbit and sturgeon muscle aldolases (EC 4.1.2.13), respectively. Although the mechanism of their interaction with PLP should be the same, these residues can be differentiated into three families on the basis of their inhibition constant Ki and rate constant k. The lysine residues of one of these families do not react with PLP in the presence of the substrates. Therefore, they are assumed to be part of the active center. In the sturgeon muscle aldolase, 3.7 substrate protected lysine residues are present. Rabbit aldolase, although tetrameric, contains only 2.8 substrate protected lysine residues. This suggests that one active center of this enzyme may be 'buried'. Structural studies showed the following sequence around the substrate protected lysine residues, in the rabbit aldolase: Gly-(Gly2, Val3)-Pyridoxyl Lys-Ile-Asp-Lys.
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PMID:Differential effects of pyridoxal 5'-phosphate on lysine residues in rabbit and sturgeon muscle aldolases. 95 52

Rabbit liver cathepsin M, a sulfhydryl proteinase similar in catalytic properties to cathepsin B, causes a decrease in the activity of rabbit muscle aldolase assayed with fructose 1,6-bisphosphate but not with fructose 1-phosphate. Proteolytic modification of aldolase by cathepsin M is limited to the removal of small peptides from the COOH-terminus, including the COOH-terminal hexapeptide NH2-Ile-Ser-Asn-His-Ala-TyrOH. Correlation of loss of aldolase activity with COOH-terminal modification indicates that only three of the four subunits of muscle aldolase contribute to the catalytic activity of the tetrameric enzyme.
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PMID:Sites of cleavage of rabbit muscle aldolase by purified cathepsin M from rabbit liver. 370 51

Several streptomycin-resistant mutants of Escherichia coli have been isolated which require exogenous isoleucine for growth. The majority of these strains were of streptomycin-dependent phenotype. If grown in the absence of streptomycin, these streptomycin-dependent auxotrophs (Sm(d-aux)) strains were unable to produce beta-galactosidase and aldolase activities and also failed to exhibit donor properties in conjugation. Genetic analysis indicated that the isoleucine requirement of these strains could be caused by a mutation at the strA locus.
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PMID:Development of auxotrophy by streptomycin-resistant mutation. 459 98

Cathepsin D inactivated aldolase at pH values between 4.2 and 5.2; the chloride, sulphate or iodide, but not citrate or acetate, salts of sodium or potassium accelerated the rate of inactivation. Cathepsin D cleaved numerous peptide bonds in the C-terminus of aldolase, but the major site of cleavage in this region was Leu354-Phe355. The most prominent peptide products of hydrolysis were Phe-Ile-Ser-Asn-His-Ala-Tyr and Phe-Ile-Ser-Asn-His. Up to 20 amino acids were removed from the C-terminus of aldolase, but no further degradation of native aldolase was observed. By contrast, extensive degradation of the 40 000-Mr subunit was observed after aldolase was denatured. The cathepsin D-inactivated aldolase cross-reacted with antibodies prepared against native aldolase and had the same thermodynamic stability as native aldolase, demonstrated by differential scanning calorimetry and fluorescence quenching of tryptophan residues. Furthermore, the cathepsin-modified and native forms of aldolase were both resistant to extensive proteolysis by other purified cellular proteinases and lysosomal extracts at pH values of 4.8-8.0.
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PMID:Action of cathepsin D on fructose-1,6-bisphosphate aldolase. 688 56

Effects of sulfaguanidine, leucine, or leucine plus isoleucine in a niacin free diet on body weight changes, liver weight, pyridine nucleotide concentrations, and activities of enzymes in mature female or immature Japanese quail were measured. The inclusion of .5% of sulfaguanidine or a high level of leucine in a niacin free diet had no influence during an 8-week period on liver pyridine nucleotide levels and the development of niacin deficiency symptoms in mature female quail. This would suggest that the mature female quail has a low requirement for dietary niacin. Immature quail were also tested to study the effects of amino acid imbalance on the induction of niacin deficiency. Although there was a marked reduction in body weight gains by the administration of leucine or leucine plus isoleucine, these treatments did not appear to accentuate niacin deficiency symptoms in these animals. Also pyridine nucleotide levels and malic enzyme, glyceraldehyde-3-phosphate dehydrogenase, and aldolase activities in liver tissues were not affected by these treatments.
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PMID:Effects of sulfaguanidine and amino acid imbalances on the induction of niacin deficiency in mature and immature Japanese quail (Coturnix coturnix japonica). 713 12

The mechanism of degradation of fructose-1,6-bisphosphate aldolase from rabbit muscle by the lysosomal proteinase cathepsin B was determined. Treatment of aldolase with cathepsin B destroys up to 90% of activity with fructose 1,6-bisphosphate as substrate, but activity with fructose 1-phosphate is slightly increased. Cathepsin L, another lysosomal thiol proteinase, and papain are also potent inactivators of aldolase, whereas inactivation is not caused by cathepsins D or H even at high concentrations, or by cathepsin B inhibited by leupeptin or iodoacetate. The cathepsin-B-treated aldolase shows no detectable change in subunit molecular weight, oligomer molecular weight or subunit interactions. Cathepsin B cleaves dipeptides from the C-terminus of th aldolase subunits. Four dipeptides are released sequentially: Ala-Tyr, Asn-His, Ile-Ser and Leu-Phe, and a maximum of five additional dipeptides may be released. There are indications that this peptidyldipeptidase activity of cathepsin B may be an important aspect of its action on protein substrates generally.
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PMID:Degradation of fructose-1,6-bisphosphate aldolase by cathepsin B. 745 1

Pea leaf chloroplast aldolase contains seven more aspartyl (asx) residues and four fewer leucine and isoleucine residues than the cytoplasmic enzyme. The two forms are therefore primary isoenzymes, differing in amino acid sequence.
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PMID:Chloroplast and Cytoplasmic Enzymes: VIII. Amino Acid Composition of the Pea Leaf Aldolases. 1666 Sep 75

Amino acids are not only fundamental protein constituents but also serve as precursors for many essential plant metabolites. Although amino acid biosynthetic pathways in plants have been identified, pathway regulation, catabolism, and downstream metabolite partitioning remain relatively uninvestigated. Conversion of Thr to Gly and acetaldehyde by Thr aldolase (EC 4.1.2.5) was only recently shown to play a role in plant amino acid metabolism. Whereas one Arabidopsis thaliana Thr aldolase (THA1) is expressed primarily in seeds and seedlings, the other (THA2) is expressed in vascular tissue throughout the plant. Metabolite profiling of tha1 mutants identified a >50-fold increase in the seed Thr content, a 50% decrease in seedling Gly content, and few other significant metabolic changes. By contrast, homozygous tha2 mutations cause a lethal albino phenotype. Rescue of tha2 mutants and tha1 tha2 double mutants by overproduction of feedback-insensitive Thr deaminase (OMR1) shows that Gly formation by THA1 and THA2 is not essential in Arabidopsis. Seed-specific expression of feedback-insensitive Thr deaminase in both tha1 and tha2 Thr aldolase mutants greatly increases seed Ile content, suggesting that these two Thr catabolic enzymes compete for a common substrate pool.
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PMID:Two Arabidopsis threonine aldolases are nonredundant and compete with threonine deaminase for a common substrate pool. 1717 52

Ignicoccus hospitalis is an autotrophic hyperthermophilic archaeon that serves as a host for another parasitic/symbiotic archaeon, Nanoarchaeum equitans. In this study, the biosynthetic pathways of I. hospitalis were investigated by in vitro enzymatic analyses, in vivo (13)C-labeling experiments, and genomic analyses. Our results suggest the operation of a so far unknown pathway of autotrophic CO(2) fixation that starts from acetyl-coenzyme A (CoA). The cyclic regeneration of acetyl-CoA, the primary CO(2) acceptor molecule, has not been clarified yet. In essence, acetyl-CoA is converted into pyruvate via reductive carboxylation by pyruvate-ferredoxin oxidoreductase. Pyruvate-water dikinase converts pyruvate into phosphoenolpyruvate (PEP), which is carboxylated to oxaloacetate by PEP carboxylase. An incomplete citric acid cycle is operating: citrate is synthesized from oxaloacetate and acetyl-CoA by a (re)-specific citrate synthase, whereas a 2-oxoglutarate-oxidizing enzyme is lacking. Further investigations revealed that several special biosynthetic pathways that have recently been described for various archaea are operating. Isoleucine is synthesized via the uncommon citramalate pathway and lysine via the alpha-aminoadipate pathway. Gluconeogenesis is achieved via a reverse Embden-Meyerhof pathway using a novel type of fructose 1,6-bisphosphate aldolase. Pentosephosphates are formed from hexosephosphates via the suggested ribulose-monophosphate pathway, whereby formaldehyde is released from C-1 of hexose. The organism may not contain any sugar-metabolizing pathway. This comprehensive analysis of the central carbon metabolism of I. hospitalis revealed further evidence for the unexpected and unexplored diversity of metabolic pathways within the (hyperthermophilic) archaea.
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PMID:Insights into the autotrophic CO2 fixation pathway of the archaeon Ignicoccus hospitalis: comprehensive analysis of the central carbon metabolism. 1740 Jul 48


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