PVAS3, a class-II ubiquitous asparagine synthetase from the common bean (Phaseolus vulgaris)
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- Parra-Peralbo, E., Pineda, M. & Aguilar, M. Mol Biol Rep (2009) 36: 2249. doi:10.1007/s11033-008-9441-y
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A gene encoding a putative asparagine synthetase (AS; EC 184.108.40.206) has been isolated from common bean (Phaseolus vulgaris). A 2.4 kb cDNA clone of this gene (PVAS3) encodes a protein of 570 amino acids with a predicted molecular mass of 64,678 Da, an isoelectric point of 6.45, and a net charge of −5.9 at pH 7.0. The PVAS3 protein sequence conserves all the amino acid residues that are essential for glutamine-dependent AS, and PVAS3 complemented an E. coli asparagine auxotroph, that demonstrates that it encodes a glutamine-dependent AS. PVAS3 displayed significant similarity to other AS. It showed the highest similarity to soybean SAS3 (92.9% identity), rice AS (73.7% identity), Arabidopsis ASN2 (73.2%) and sunflower HAS2 (72.9%). A phylogenetic analysis revealed that PVAS3 belongs to class-II asparagine synthetases. Expression analysis by real-time RT-PCR revealed that PVAS3 is expressed ubiquitously and is not repressed by light.