Cloning and characterization of the P subunit of glycine decarboxylase from pea (Pisum sativum).
A pea leaf cDNA library constructed in lambda gt11 was screened with an antibody raised to the P subunit of glycine decarboxylase. One of the positive clones isolated was sequenced and shown to contain an open reading frame, which encoded the entire P subunit polypeptide. Aligning the deduced amino acid sequence with the amino acid sequence determined directly from the NH2 terminus of the mature P subunit shows the presence of a putative 86 amino acid leader sequence, presumably required for import into the mitochondria, and gives a Mr of the mature protein of 105,000. Comparison of this deduced amino acid sequence with the sequence of a pyridoxal phosphate-containing peptide isolated from the P subunit of chicken liver glycine decarboxylase shows remarkable conservation. The P subunit, however, shows little sequence homology with other published amino acid decarboxylases. Expression of the P subunit mRNA shows a pattern very similar to that of the corresponding polypeptide: it is strongly light induced and is expressed at a much higher level in leaves than in other tissues. Southern blot analysis suggests that the P subunit is encoded by a small multigene family.
Cambridge Laboratory, Agricultural and Food Research Council, John Innes Centre, Norwich, United Kingdom.
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Turner
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Ireland
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Rawsthorne
D000594:Amino Acid Oxidoreductases / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D002645:Chickens; D003001:Cloning, Molecular / Q000379:methods; D007887:Fabaceae / Q000201:enzymology / Q000235:genetics*; D015723:Gene Library; D050841:Glycine Dehydrogenase (Decarboxylating); D008099:Liver / Q000201:enzymology; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010946:Plants, Medicinal; D011061:Poly A / Q000235:genetics / Q000302:isolation & purification; D012333:RNA, Messenger / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000378:metabolism; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid
D046911:Macromolecular Substances; D012333:RNA, Messenger; D011994:Recombinant Proteins; D011061:Poly A; D000594:Amino Acid Oxidoreductases; D050841:Glycine Dehydrogenase (Decarboxylating)