Functional consequences of exchanging domains between LacI and PurR are mediated by the intervening linker sequence.

ABSTRACT: Homologue function can be differentiated by changing residues that affect binding sites or long-range interactions. LacI and PurR are two proteins that represent the LacI/GalR family (>500 members) of bacterial transcription regulators. All members have distinct DNA-binding and regulatory domains linked by approximately 18 amino acids. Each homologue has specificity for different DNA and regulatory effector ligands; LacI and PurR also exhibit differences in allosteric communication between DNA and effector binding sites. A comparative study of LacI and PurR suggested that alterations in the interface between the regulatory domain and linker are important for differentiating their functions. Four residues (equivalent to LacI positions 48, 55, 58, and 61) appear particularly important for cr

SUBMITTER: Tungtur S 

PROVIDER: S-EPMC2084478 | biostudies-literature | 2007 Jul

REPOSITORIES: biostudies-literature