Split target specificity of ResT: a design for protein delivery, site selectivity and regulation of enzyme activity?
The ResT telomere resolvase is responsible for maintaining the hairpin telomeres that cap the linear chromosome and minichromosomes of Borrelia burgdorferi. This enzyme acts at the tandem telomere junctions present within circular dimers resulting from DNA replication. ResT mediates the transesterification steps of resolution using a constellation of active site residues similar to that found in tyrosine recombinases and type IB topoisomerases. By combining this reaction mechanism with a hairpin binding module in its N-terminal domain, ResT reduces a fused telomere dimer into two hairpin monomers. ResT displays a split DNA binding specificity, with the N- and C-terminal domains targeting distinct regions of the telomere. This bi-specificity in binding is likely to be important in protein delivery, substrate selection and regulation of enzyme activity.
Jayaram
Makkuni
M
Section of Molecular Genetics and Microbiology, University of Texas at Austin, Austin, TX 78712, USA. jayaram@icmb.utexas.edu
D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D025065:Borrelia burgdorferi / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D004261:DNA Replication; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism; D004706:Endodeoxyribonucleases / Q000235:genetics / Q000378:metabolism*; D016680:Genome, Bacterial; D008957:Models, Genetic; D011485:Protein Binding; D045522:Recombinases / Q000235:genetics / Q000378:metabolism; D016615:Telomere / Q000378:metabolism
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D045522:Recombinases; D004706:Endodeoxyribonucleases; C446515:ResT protein, Borrelia