BBB : Vol. 66 (2002) , No. 5 pp.1057-1068

Cloning and Sequencing of the Genes Encoding Cyclic Tetrasaccharide-synthesizing Enzymes from Bacillus globisporus C11

Hajime AGA¹⁾, Kazuhiko MARUTA¹⁾, Takuo YAMAMOTO¹⁾, Michio KUBOTA¹⁾, Shigeharu FUKUDA¹⁾, Masashi KURIMOTO¹⁾ and Yoshio TSUJISAKA¹⁾

1) Amase Institute, Hayashibara Biochemical Laboratories

(Received December 3, 2001)
(Accepted January 5, 2002)

The genes for isomaltosyltransferase (CtsY) and 6-glucosyltransferase (CtsZ), involved in synthesis of a cyclic tetrasaccharide from α-glucan, have been cloned from the genome of Bacillus globisporus C11. The amino-acid sequence deduced from the ctsY gene is composed of 1093 residues having a signal sequence of 29 residues in its N-terminus. The ctsZ gene encodes a protein consisting of 1284 residues with a signal sequence of 35 residues. Both of the gene products show similarities to α-glucosidases belonging to glycoside hydrolase family 31 and conserve two aspartic acids corresponding to the putative catalytic residues of these enzymes. The two genes are linked together, forming ctsYZ. The DNA sequence of 16,515 bp analyzed in this study contains four open reading frames (ORFs) upstream of ctsYZ and one ORF downstream. The first six ORFs, including ctsYZ, form a gene cluster, ctsUVWXYZ. The amino-acid sequences deduced from ctsUV are similar in to a sequence permease and a sugar-binding protein for the sugar transport system from Thermococcus sp. B1001. The third ctsW encodes a protein similar to CtsY, suggested to be another isomaltosyltransferase preferring panose to high-molecular-mass substrates.

Key words:

6-glucosyltransferase; isomaltosyltransferase; cyclic tetrasaccharide; Bacillus globisporus

	To cite this article:
	Hajime AGA, Kazuhiko MARUTA, Takuo YAMAMOTO, Michio KUBOTA, Shigeharu FUKUDA, Masashi KURIMOTO and Yoshio TSUJISAKA, “Cloning and Sequencing of the Genes Encoding Cyclic Tetrasaccharide-synthesizing Enzymes from Bacillus globisporus C11”, Biosci. Biotechnol. Biochem., Vol. 66, 1057-1068 (2002) .

	doi:10.1271/bbb.66.1057
	JOI JST.JSTAGE/bbb/66.1057