ISSN:
1432-072X
Keywords:
Rhizobium
;
Bacteriophage
;
Electron Microscopy
;
Fine Structure
;
Optical Diffraction
;
DNA
;
“Sticky Ends”
;
Partial Denaturation
;
AT-GC-Map
;
Computer Application
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Bacteriophage 16-6-12 of Rhizobium lupini has a long, non-contractile tail and a head which is hexagonal in outline. The tail is 140 nm in length, 11 nm in diameter, and carries a short terminal fiber. Analysis of the tail structure by optical diffraction indicates that it is of the helical “stacked disc” type. After phenol-extraction from purified particles, the DNA of phage 16-6-12 can circularize in vitro. No significant difference in contour length was observed between the linear (14.34±0.28 μm) and circular (14.44±0.24 μm) forms of molecules. After partial denaturation with alkali an AT-GC-map was constructed, which shows an asymmetric distribution of AT- and GC-rich regions. It is concluded that this phage DNA can circularize due to the presence of cohesive ends and that it is not circularly permuted.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00447320
