Poly(3-hydroxybutyrate) depolymerases bind to their substrate by a C-terminal located substrate binding site.

A Behrends; B Klingbeil; D Jendrossek

doi:10.1111/j.1574-6968.1996.tb08479.x

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Poly(3-hydroxybutyrate) depolymerases bind to their substrate by a C-terminal located substrate binding site.

A Behrends·B Klingbeil·D Jendrossek

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Abstract

Binding of (i) purified wild-type poly(3-hydroxybutyrate) (PHB) depolymerase PhaZ4 of Pseudomonas lemoignei, (ii) a purified truncated form of PhaZ4, which lacked 55 C-terminal amino acids and (iii) commercial lactate dehydrogenase to aqueous suspensions of PHB, chitin or cellulose was studied. Only the wild-type PHB depolymerase was specifically able to bind to PHB granules. No other combination of protein and polymeric substrate resulted in polymer-bound protein. Similar results were obtained for other PHB depolymerases. We concluded that the C-terminal amino acids of PHB depolymerases represent a PHB-specific binding domain or at least an essential part of it.

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Amino Acid Sequence Binding Sites Carboxylic Ester Hydrolases Escherichia coli Molecular Sequence Data Mutagenesis Pseudomonas Recombinant Proteins Sequence Deletion Sequence Homology, Amino Acid Substrate Specificity Journal Article Research Support, Non-U.S. Gov't

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A Behrends, B Klingbeil, D Jendrossek. 1996-10-01. Poly(3-hydroxybutyrate) depolymerases bind to their substrate by a C-terminal located substrate binding site.. https://doi.org/10.1111/j.1574-6968.1996.tb08479.x

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