Thermostable α-galactosidase from Thermotoga neapolitana: cloning, sequencing and expression

• Published in: FEMS microbiology letters 1998-06, Vol.163 (1), p.37-42
• Main Authors: King, Michael R, Yernool, Dinesh A, Eveleigh, Douglas E, Chassy, Bruce M
• Format: Article
• Language: English
• Subjects: Alpha-galactosidase; alpha-Galactosidase - chemistry; alpha-Galactosidase - genetics; alpha-Galactosidase - isolation & purification; Amino Acid Sequence; Bacteriology; Base Sequence; Biological and medical sciences; Cloning, Molecular; Enzyme Stability; Escherichia coli - genetics; Fundamental and applied biological sciences. Psychology; genbank/af011400; Genes, Bacterial - genetics; Gram-Negative Anaerobic Bacteria - enzymology; Gram-Negative Anaerobic Bacteria - genetics; Hot Temperature; Hydrolysis; industrial applications; Melibiose - metabolism; Metabolism. Enzymes; Microbiology; Molasses; Molecular Sequence Data; Molecular Weight; Recombinant Fusion Proteins; Sequence Analysis; Sequence Analysis, DNA; Sequence Homology, Amino Acid; Soy molasses; soybean products; Thermostable; Thermotoga
• ISSN: 0378-1097; 1574-6968
• DOI: 10.1016/S0378-1097(98)00148-7

A gene encoding a thermostable α-galactosidase from the hyperthermophile Thermotoga neapolitana was cloned and sequenced. Sequence analysis showed that the 552-amino acid protein is similar to Escherichia coli Raf type α-galactosidase and belongs to Family 36 of the glycosyl hydrolases. Recombinant α-galactosidase expressed in E. coli has a molecular mass of ca. 61 kDa, and an optimum activity at 93°C at pH 7.0. The enzyme is highly thermostable and retains 75% of activity after heating to 80°C for 4 h. The potential application of the enzyme to high temperature processing of soy molasses has been demonstrated.