Abstract
The Z gene is a structural gene which specifies the polypeptide monomer of β-galactosidase. This enzyme normally exists as a polymer of four identical chains with a molecular weight for the complete, native pro-tein of 540,000 (cf. Zabin and Fowler, 1970). In Figure 1, the double line represents the gene and the single line represents the corresponding polypeptide chain. Above the gene terminator mutant strains are listed. Polypeptide fragments produced by each of these have been detected by immunological and complementation tests. Molecular weights have been determined in sucrose or urea-sucrose gradients and in several cases by sedimentation equilibrium (Fowler and Zabin, 1966; Brown et al., 1967; Berg et al., 1970; Morrison and Zipser, 1970). The approximate number of residues in the polypeptide chain corresponding to the mutated site is shown below the single line; this was calculated based on an average amino acid residue weight of 115. The amino acid sequences of the first thirteen and the last ten residues have been reported (Zabin and Fowler, 1972).
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© 1974 Springer Science+Business Media New York
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Zabin, I. (1974). The lac Z gene of Escherichia coli . In: King, R.C. (eds) Bacteria, Bacteriophages, and Fungi. Springer, Boston, MA. https://doi.org/10.1007/978-1-4899-1710-2_9
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DOI: https://doi.org/10.1007/978-1-4899-1710-2_9
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