ISSN:
0952-3499
Keywords:
Chemistry
;
Biochemistry and Biotechnology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Medicine
Notes:
The reversible binding of phage G13, a φX174-like single-strand DNA phage, to a 3H-labeled nonasaccharide from the lipopolysaccharide of its natural host Esacherichia coli C was studied with equilibrium dialysis. The binding constant (Ka) was determined to 1.3 × 107 M-1 in Scatchard and Lineweaver-Burk plots. Approximately one saccharide bound per G13 phage particle which suggests that only one of the 12 spikes in each G13 virion was engaged in the phage/receptor saccharide interaction. Equilibrium dialysis inhibition experiments with saccharides from lipopolysaccharides of an isogenic series of Salmonella typhimurium mutants showed that hepta- and pentasaccharides from two G13-sensitive bacteria, i.e., with efficiencies of plating of 0.1-1.0 compared to E. coli C, were efficient inhibitors with Ka-values ≥ 1.2 × 107 M-1. The octa- and hexasaccharides from two G13 resistant strains, with efficiency of plating ≤ × 10-4, were either 〉 1000-fold of 〉 15-fold less efficient as inhibitors with Ka-values ≤8.8 - 105 M-1. The results show that phage G13 binds in a specific and reversible way to penta-, hepta-, and nonasaccharides from G13 sensitive bacteria with the specificity residing in the hexose and heptose region of the core lipopolysaccharide.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jmr.300020104
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