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Genetics. Mar 1987; 115(3): 431–439.
PMCID: PMC1216346

Cryptic Genes for Cellobiose Utilization in Natural Isolates of Escherichia coli

Abstract

The ECOR collection of natural Escherichia coli isolates was screened to determine the proportion of strains that carried functional, cryptic and nonfunctional genes for utilization of the three β-glucoside sugars, arbutin, salicin and cellobiose. None of the 71 natural isolates utilized any of the β-glucosides. Each strain was subjected to selection for utilization of each of the sugars. Only five of the isolates were incapable of yielding spontaneous β-glucoside-utilizing mutants. Forty-five strains yielded cellobiose+ mutants, 62 yielded arbutin+ mutants, and 58 strains yielded salicin+ mutants. A subset of the mutants was screen by mRNA hybridization to determine whether they were expressing either the cel or the bgl β-glucoside utilization operons of E. coli K12. Two cellobiose+ and two arbutin+ -salicin+ strains failed to express either of these known operons. It is concluded that there are at least four gene clusters specifying β-glucoside utilization functions in E. coli populations, and that all of these are normally cryptic. It is estimated that in any random isolate the probability of any particular cluster having been irreversibly inactivated by the accumulation of random mutations is about 0.5.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Li WH. Retention of cryptic genes in microbial populations. Mol Biol Evol. 1984 Feb;1(2):213–219. [PubMed]
  • Morishita T, Fukada T, Shirota M, Yura T. Genetic basis of nutritional requirements in Lactobacillus casei. J Bacteriol. 1974 Dec;120(3):1078–1084. [PMC free article] [PubMed]
  • Reynolds AE, Felton J, Wright A. Insertion of DNA activates the cryptic bgl operon in E. coli K12. Nature. 1981 Oct 22;293(5834):625–629. [PubMed]
  • Southern EM. Detection of specific sequences among DNA fragments separated by gel electrophoresis. J Mol Biol. 1975 Nov 5;98(3):503–517. [PubMed]

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