Molecular cloning and characterization of an alpha-amylase occurring in the pulp of ripening bananas and its expression in Pichia pastoris.
Alpha-amylases (EC 3.2.1.1) are glycosyl hydrolases with endoglycolytic activity on the alpha-1,4-d-glucosidic linkages in starch. In bananas, the mobilization of starch accounts for sugar accumulation during ripening, and among several hydrolytic enzymes, alpha-amylase is the only enzyme argued to be able to attack the intact granules, indicating a pivotal role for this enzyme. A 1953 bp full-length banana alpha-amylase cDNA (MAmy), encoded for a sequence of 416 amino acids, was cloned and used for heterologous expression in Pichia pastoris. The cloned MAmy presented the highly conserved motifs common to alpha-amylases, and the amylolytic activity of the extracts from yeast transformed with MAmy demonstrated that it encodes for a functional alpha-amylase, suggesting a putative role for this gene in starch degradation during fruit ripening.
Junior
Adair Vieira
AV
Laboratório de Química, Bioquímica e Biologia Molecular de Alimentos, Departamento de Alimentos e Nutrição Experimental, FCF, Universidade de São Paulo, Avenida Lineu Prestes 580, bloco 14, São Paulo CEP 05508-000, SP, Brazil.
do Nascimento
João Roberto Oliveira
JR
Lajolo
Franco Maria
FM
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D005638:Fruit / Q000201:enzymology* / Q000254:growth & development; D015870:Gene Expression; D008969:Molecular Sequence Data; D028521:Musa / Q000201:enzymology*; D010802:Phylogeny; D010843:Pichia / Q000201:enzymology*; D016133:Polymerase Chain Reaction; D014162:Transfection; D000516:alpha-Amylases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
D018076:DNA, Complementary; D000516:alpha-Amylases