Starch-synthase III family encodes a tandem of three starch-binding domains

PALOPOLI, N.; BUSI, M. V.; FORNASARI, M. S.; DIEGO FABIAN GOMEZ CASATI; UGALDE, R.; PARISI, G.

PROTEINS: STRUCTURE, FUNCTION AND GENETICS

Wiley-Liss

Año: 2006 vol. 65 p. 27 - 31

0887-3585

The starch-synthase III (SSIII), with a total of 1025 residues, is one of the enzymes involved in plants starch synthesis. SSIII from Arabidopsis thaliana contains a putative N-terminal transit peptide followed by a 557-amino acid SSIIIspecific domain (SSIII-SD) with three internal repeats and a C-terminal catalytic domain of 450 amino acids. Here, using computational characterization techniques, we show that each of the three internal repeats encodes a starch-binding domain (SBD). Although the SSIII from A. thaliana and its close homologous proteins show no detectable sequence similarity with characterized SBD sequences, the amino acid residues known to be involved in starch binding are well conserved.Arabidopsis thaliana contains a putative N-terminal transit peptide followed by a 557-amino acid SSIIIspecific domain (SSIII-SD) with three internal repeats and a C-terminal catalytic domain of 450 amino acids. Here, using computational characterization techniques, we show that each of the three internal repeats encodes a starch-binding domain (SBD). Although the SSIII from A. thaliana and its close homologous proteins show no detectable sequence similarity with characterized SBD sequences, the amino acid residues known to be involved in starch binding are well conserved.contains a putative N-terminal transit peptide followed by a 557-amino acid SSIIIspecific domain (SSIII-SD) with three internal repeats and a C-terminal catalytic domain of 450 amino acids. Here, using computational characterization techniques, we show that each of the three internal repeats encodes a starch-binding domain (SBD). Although the SSIII from A. thaliana and its close homologous proteins show no detectable sequence similarity with characterized SBD sequences, the amino acid residues known to be involved in starch binding are well conserved.A. thaliana and its close homologous proteins show no detectable sequence similarity with characterized SBD sequences, the amino acid residues known to be involved in starch binding are well conserved.