ABSTRACT
Genes related to trehalose biosynthesis from a bacterial strain Micrococcus luteus which can convert partially hydrolyzed starch into trehalose were cloned.Full sequence of gene (MtreY) encoding trehalose maltooligosyl trehalose synthase (MTSase) and partial sequence of gene (MtreZ) encoding maltooligosyl trehalose trehalohydrolase (MTHase) were got using PCR combined non-random shotgun method.Sequence analysis of MtreY predicts a 2370bp open reading frame encoding a protein of 790 amino acids with a predicted molecular weight of 86734 Da.Homologous analysis shows that this new gene has the same conservative motifs with ?-amylase family enzymes.The MtreY gene was expressed in E.coli, and the expression product has the anticipative enzyme activity.