Measurements of DNA lengths remaining in a viral capsid after osmotically suppressed partial ejection.
The effect of external osmotic pressure on the extent of DNA ejection from bacteriophage-lambda was recently investigated (Evilevitch et al., 2003). The total length of DNA ejected was measured via the 260-nm absorption by free nucleotides, after opening of the capsids in the presence of varying amounts of polyethylene glycol 8000 and DNase I. As a function of osmolyte concentration, this absorption was shown to decrease progressively, ultimately vanishing completely for a sufficiently high external osmotic pressure. In this work we report the results of both sedimentation and gel analysis of the length of DNA remaining inside the capsids, as a function of osmolyte concentration. It is confirmed in this way that the progressive inhibition of DNA ejection corresponds to partial ejection from all of the capsids.
Evilevitch
Alex
A
Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, USA.
Gober
James W
JW
Phillips
Martin
M
Knobler
Charles M
CM
Gelbart
William M
WM
D000042:Absorption; D000956:Antigens, Viral / Q000737:chemistry*; D010582:Bacteriophage lambda / Q000378:metabolism; D002213:Capsid / Q000737:chemistry*; D020285:Cryoelectron Microscopy; D004247:DNA / Q000737:chemistry*; D003850:Deoxyribonuclease I / Q000737:chemistry; D004586:Electrophoresis; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000378:metabolism; D009995:Osmosis; D009997:Osmotic Pressure; D019800:Phenol / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D014466:Ultraviolet Rays
D000956:Antigens, Viral; D019800:Phenol; D011092:Polyethylene Glycols; D004247:DNA; D003850:Deoxyribonuclease I