Dataset Information

Interaction between the endoglucanase CelA and the scaffolding protein CipC of the Clostridium cellulolyticum cellulosome.

ABSTRACT: The 5' end of the cipC gene, coding for the N-terminal part of CipC, the scaffolding protein of Clostridium cellulolyticum ATCC 35319, was cloned and sequenced. It encodes a 586-amino-acid peptide, including several domains: a cellulose-binding domain, a hydrophilic domain, and two hydrophobic domains (cohesin domains). Sequence alignments showed that the N terminus of CipC and CbpA of C. cellulovorans ATCC 35296 have the same organization. The mini-CipC polypeptide, containing a cellulose-binding domain, hydrophilic domain 1, and cohesin domain 1, was overexpressed in Escherichia coli and purified. The interaction between endoglucanase CelA, with (CelA2) and without (CelA3) the characteristic clostridial C-terminal domain called the duplicated-segment or dockerin domain, and the mini-CipC polypeptide was monitored by two different methods: the interaction Western blotting (immunoblotting) method and binding assays with biotin-labeled protein. Among the various forms of CelA (CelA2, CelA3, and an intermediary form containing only part of the duplicated segment), only CelA2 was found to interact with cohesin domain 1 of CipC. The apparent equilibrium dissociation constant of the CelA2-mini-CipC complex was 7 x 10(-9)M, which indicates that there exists a high affinity between these two proteins.

SUBMITTER: Pages S

PROVIDER: S-EPMC177936 | biostudies-other | 1996 Apr

REPOSITORIES: biostudies-other

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Interaction between the endoglucanase CelA and the scaffolding protein CipC of the Clostridium cellulolyticum cellulosome.

Pagès S S Belaich A A Tardif C C Reverbel-Leroy C C Gaudin C C Belaich J P JP

Journal of bacteriology 19960401 8

The 5' end of the cipC gene, coding for the N-terminal part of CipC, the scaffolding protein of Clostridium cellulolyticum ATCC 35319, was cloned and sequenced. It encodes a 586-amino-acid peptide, including several domains: a cellulose-binding domain, a hydrophilic domain, and two hydrophobic domains (cohesin domains). Sequence alignments showed that the N terminus of CipC and CbpA of C. cellulovorans ATCC 35296 have the same organization. The mini-CipC polypeptide, containing a cellulose-bindi ...[more]

PMID: 8636029

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Dataset Information

Interaction between the endoglucanase CelA and the scaffolding protein CipC of the Clostridium cellulolyticum cellulosome.

Publications

Interaction between the endoglucanase CelA and the scaffolding protein CipC of the Clostridium cellulolyticum cellulosome.

Similar Datasets

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