BBB : Vol. 65 (2001) , No. 3 pp.548-554

Sequence of the Clostridium thermocellum Mannanase Gene man26B and Characterization of the Translated Product

Junji KUROKAWA¹⁾, Eiakalak HEMJINDA¹⁾, Takamitsu ARAI¹⁾, Shuichi KARITA²⁾, Tetsuya KIMURA¹⁾, Kazuo SAKKA¹⁾ and Kunio OHMIYA¹⁾

1) Faculty of Bioresources, Mie University
2) Center for Molecular Biology and Genetics, Mie University

(Received September 4, 2000)
(Accepted November 1, 2000)

The man26B gene of Clostridium thermocellum strain F1 was found in pKS305, which had been selected as a recombinant plasmid conferring endoglucanase activity on Escherichia coli. The open reading frame of man26B consists of 1,773 nucleotides encoding a protein of 591 amino acids with a predicted molecular weight of 67,047. Man26B is a modular enzyme composed of an N-terminal signal peptide and three domains in the following order: a mannan-binding domain, a family 26 mannanase domain, and a dockerin domain responsible for cellulosome assembly. We found that this gene was a homologue of the man26A gene of C. thermocellum strain YS but that there were insertion or deletion mutations that caused a frame-shift mutation affecting a stretch of 26 amino acids in the catalytic domain. Man26B devoid of the dockerin domain was constructed and purified from a recombinant E. coli, and its enzyme properties were examined. Immunological analysis indicated that Man26B was a catalytic component of the C. thermocellum F1 cellulosome.

Key words:

Clostridium thermocellum; mannanase; cellulosome

	To cite this article:
	Junji KUROKAWA, Eiakalak HEMJINDA, Takamitsu ARAI, Shuichi KARITA, Tetsuya KIMURA, Kazuo SAKKA and Kunio OHMIYA, “Sequence of the Clostridium thermocellum Mannanase Gene man26B and Characterization of the Translated Product”, Biosci. Biotechnol. Biochem., Vol. 65, 548-554 (2001) .

	doi:10.1271/bbb.65.548
	JOI JST.JSTAGE/bbb/65.548