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A homolog of Escherichia coli RecA protein in plastids of higher plants.

ABSTRACT: Studies of chloroplast DNA variations, and several direct experimental observations, indicate the existence of recombination ability in algal and higher plant plastids. However, no studies have been done of the biochemical pathways involved. Using a part of a cyanobacterial recA gene as a probe in Southern blots, we have found homologous sequences in total DNA from Pisum sativum and Arabidopsis thaliana and in a cDNA library from Arabidopsis. A cDNA was cloned and sequenced, and its predicted amino acid sequence is 60.7% identical to that of the cyanobacterial RecA protein. This finding is consistent with our other results showing both DNA strand transfer activity and the existence of a protein of the predicted molecular mass crossreactive with antibodies to Escherichia coli RecA in the stroma of pea chloroplasts.

SUBMITTER: Cerutti H

PROVIDER: S-EPMC49857 | biostudies-other | 1992 Sep

REPOSITORIES: biostudies-other

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A homolog of Escherichia coli RecA protein in plastids of higher plants.

Cerutti H H Osman M M Grandoni P P Jagendorf A T AT

Proceedings of the National Academy of Sciences of the United States of America 19920901 17

Studies of chloroplast DNA variations, and several direct experimental observations, indicate the existence of recombination ability in algal and higher plant plastids. However, no studies have been done of the biochemical pathways involved. Using a part of a cyanobacterial recA gene as a probe in Southern blots, we have found homologous sequences in total DNA from Pisum sativum and Arabidopsis thaliana and in a cDNA library from Arabidopsis. A cDNA was cloned and sequenced, and its predicted am ...[more]

PMID: 1518831

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Analysis of Escherichia coli RecA interactions with LexA, lambda CI, and UmuD by site-directed mutagenesis of recA.

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