Models of bacteriophage DNA packaging motors.
An ATP-dependent motor drives a DNA genome into a bacteriophage capsid during morphogenesis of double-stranded DNA bacteriophages both in vivo and in vitro. The DNA molecule enters the capsid through a channel in the center of a symmetric protein ring called a connector. Mechanisms in two classes have been proposed for this motor: (1) An ATP-driven rotating connector pulls a DNA molecule via serial power strokes. (2) The connector rectifies DNA motion that is either thermal, biased thermal, or oscillating electrical field-induced (motor-ratchet hypothesis). Mechanisms in the first class have previously been proposed to explain the detailed structure of DNA packaging motors. The present study demonstrates that the motor-ratchet hypothesis also explains the current data, including data in the following categories: biochemical genetics, energetics, structure, and packaging dynamics.
Serwer
Philip
P
Department of Biochemistry, University of Texas Health Science Center, San Antonio, TX 78229-3900, USA. serwer@uthscsa.edu
D000255:Adenosine Triphosphate / Q000378:metabolism; D001435:Bacteriophages / Q000502:physiology* / Q000648:ultrastructure*; D055592:Biophysical Phenomena; D001703:Biophysics; D004247:DNA / Q000648:ultrastructure*; D016679:Genome, Viral; D006358:Hot Temperature; D008954:Models, Biological; D013696:Temperature
D000255:Adenosine Triphosphate; D004247:DNA