Evolution of enzyme structure.

B S Hartley

doi:10.1098/rspb.1979.0078

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Evolution of enzyme structure.

B S Hartley

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Abstract

Three-dimensional structures of enzymes offer evidence about their evolution. There are clear examples of divergent families (e.g. mammalian serine proteases) and convergence (e.g. chymotrypsin and subtilisin). Topological similarities in dehydrogenases may reflect an ancient divergence or merely chemical constraints on protein architectures. Further experimental evidence is desirable to back up arguments based on molecular morphology. By growing microorganisms on novel foodstuffs in a chemostat, one can focus selective pressure on a specific enzyme activity. Experiments will be described in which such pressure is focused on pentitol metabolism. Examination of the fine structure of the genes responsible for this pentitol metabolism has given clues about the volution of metabolic pathways.

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Amino Acid Sequence Biological Evolution Chemical Phenomena Chemistry Enzymes Escherichia coli Klebsiella pneumoniae Molecular Biology Molecular Conformation Operon Peptide Hydrolases Ribitol Serine Species Specificity Streptomyces griseus Sugar Alcohols Comparative Study Journal Article

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B S Hartley. 1979-09-21. Evolution of enzyme structure.. https://doi.org/10.1098/rspb.1979.0078

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