International Journal of Biochemistry and Biotechnology

ISSN 2169-3048

International Journal of Biochemistry and Biotechnology Vol. 1 (1), pp.012-018, March, 2012.  © International Scholars Journals

Full Length Research Paper

Peptide sequences from seed storage proteins of tepary bean (Phaseolus acutifolius) accession G40199 demonstrate the presence of multiple variants of APA proteins

Kusolwa PM and Myers JR.

1Department of Crop Science and Production, Sokoine University of Agriculture, Box 3005, Chuo Kikuu , Morogoro Tanzania.

2 Department of horticulture, Oregon State University, 4017 ALS Bldg, Corvallis, OR 97331-7304, USA

*Corresponding Author’s E-mail: [email protected]

Received March 1, 2012; Accepted March 26, 2012

 Abstract

Proteomic analysis of the expression of seed storage proteins was performed in wild tepary beans (P. acutifolius) accession G40199. The interspecific backcross progenies were obtained from the cross between G40199 and cultivated common bean (Phaseolus vulgaris) cultivars ICA Pijao and/or Rojo. Mature seeds from interspecific backcross progenies and G40199 were used to isolate seed storage proteins. Seed storage profiles obtained by  SDS-PAGE, and bands were isolated and used for MS/MS-ES peptide sequencing and analysis. Peptide peaks and their amino acids sequences demonstrated that both the interspecific backcross progenies and G40199 contain arcelins and arcelin-like (ARL2) proteins that are co-expressed with other proteins of the arcelin, -amylase inhibitor and phytohemagglutinin (APA) locus. Arcelin and ARL2 proteins previously obtained from a wild tepary bean accession of this APA were the predominant types detected in the wild tepary bean accession G40199 demonstrating the presence of multiple arcelin-like proteins as the major seed storage proteins. The occurrence of multiple variants of the APA seed storage proteins in a single accession presents an important opportunity for exploration of antibiosis proteins in breeding for resistance to bean bruchids, major storage pests in common beans in the tropics.

Key words: APA locus, arcelin, Acanthoscellides obtectus, Zabrotes subfasciatus, peptides, tepary beans, bruchid resistance.