Abstract
Anderson, D. L. (University of Minnesota, Minneapolis), D. D. Hickman, and B. E. Reilly. Structure of Bacillus subtilis bacteriophage
29 and the length of
29 deoxyribonucleic acid. J. Bacteriol. 91:2081–2089. 1966—Bacillus subtilis bacteriophage
29 were negatively stained with phosphotungstic acid. The head of
29 has a hexagonal outline with a flattened base, and is about 315 A wide and 415 A in length. The virus has an intricate tail about 325 A in length. Twelve spindle-shaped appendages are attached to the lower of two collars which comprise the proximal portion of the tail. The distal 130 A of the tail axis has a diameter of about 60 A and is larger in diameter than the axis of the upper portion of the tail. Comparison of electron microscopic counts of
29 with plaque-forming units indicated that about 50% of the microscopic entities were infective. Phenol-extracted
29 deoxyribonucleic acid (DNA) molecules were prepared for electron microscopy by the cytochrome c film technique of Kleinschmidt et al. Measurement of contour lengths of DNA molecules from three preparations gave skewed distributions of lengths with observed modal class values ranging from 5.7 to 5.9 μ. Assuming that
29 DNA is a double helix in the B form, the corresponding molecular weights would be 10.9 × 106 to 11.3 × 106 daltons. The largest DNA molecules would have a volume of 1.9 × 107 A3 which is about 25% greater than the estimated 1.4 × 107 A3 internal volume of the phage head.
29 and the length of
29 deoxyribonucleic acid. J. Bacteriol. 91:2081–2089. 1966—Bacillus subtilis bacteriophage
29 were negatively stained with phosphotungstic acid. The head of
29 has a hexagonal outline with a flattened base, and is about 315 A wide and 415 A in length. The virus has an intricate tail about 325 A in length. Twelve spindle-shaped appendages are attached to the lower of two collars which comprise the proximal portion of the tail. The distal 130 A of the tail axis has a diameter of about 60 A and is larger in diameter than the axis of the upper portion of the tail. Comparison of electron microscopic counts of
29 with plaque-forming units indicated that about 50% of the microscopic entities were infective. Phenol-extracted
29 deoxyribonucleic acid (DNA) molecules were prepared for electron microscopy by the cytochrome c film technique of Kleinschmidt et al. Measurement of contour lengths of DNA molecules from three preparations gave skewed distributions of lengths with observed modal class values ranging from 5.7 to 5.9 μ. Assuming that
29 DNA is a double helix in the B form, the corresponding molecular weights would be 10.9 × 106 to 11.3 × 106 daltons. The largest DNA molecules would have a volume of 1.9 × 107 A3 which is about 25% greater than the estimated 1.4 × 107 A3 internal volume of the phage head.

This article has been