The bacteriophage T7 helicase is a ring-shaped hexameric motor protein that unwinds double-stranded DNA during DNA replication and recombination. To accomplish this it couples energy from the nucleotide hydrolysis cycle to translocate along one of the DNA strands. Here, we combine computational biology with new biochemical measurements to infer the following properties of the T7 helicase: (1) a...

The aim of this study was to evaluate utilization of chemical energy in relation to myocardial mechanics in variably afterloaded contractions of cardiac muscle by determining total energy utilization (—P) in the absence of energy production. Right ventricular papillary muscles of cats were equilibrated at 26°C in a myograph in Krebs' solution while contracting isometrically (12/ min). Following...

Background: Human immunodeficiency virus (HIV-1) exclusively selects and utilizes tRNALys,3 as the primer for initiation of reverse transcription. Several elements within the TΨC stem loop of tRNALys,3 are postulated to be important for selection and use in reverse transcription. The posttranscriptional modification at nucleotide 58 could play a role during plus-strand synthesis to stop reverse...