Cloning and analysis of a bifunctional methyltransferase/restriction endonuclease TspGWI, the prototype of a Thermus sp. enzyme family.

ABSTRACT:

Background

Restriction-modification systems are a diverse class of enzymes. They are classified into four major types: I, II, III and IV. We have previously proposed the existence of a Thermus sp. enzyme family, which belongs to type II restriction endonucleases (REases), however, it features also some characteristics of types I and III. Members include related thermophilic endonucleases: TspGWI, TaqII, TspDTI, and Tth111II.

Results

Here we describe cloning, mutagenesis and analysis of the prototype TspGWI enzyme that recognises the 5'-ACGGA-3' site and cleaves 11/9 nt downstream. We cloned, expressed, and mutagenised the tspgwi gene and investigated the properties of its product, the bifunctional TspGWI restriction/modification enzyme. Since TspGWI does not cleave DNA compl

SUBMITTER: Zylicz-Stachula A 

PROVIDER: S-EPMC2700111 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature