TY - JOUR
T1 - Dominant constitutive mutations in malT, the positive regulator gene of the maltose regulon in Escherichia coli
AU - Débarbouillé, M.
AU - Shuman, H. A.
AU - Silhavy, T. J.
AU - Schwartz, M.
N1 - Funding Information:
We thank Jon Beckwith in whose laboratory this work was initiated. His constructive criticisms were always of great help. This work was supported by a National Science Foundation (PCM76-21955) and an American Cancer Society grant (VC13F) to Jon Beckwith and by a grant of the Delegation G&r&ale i%laRecherche Scientifique et Technique (75 7 0039) (to M. S.). One of the authors (H. S.) was supported by a National Research Service award (5T32GM07306-02). One of the authors (T. S.) is a fellow of the Jane Coffin Childs Memorial Fund for Medical Research. The “Unite de GBn&ique Moleculairn” is part of the Laboratoire Associk no. 270 (CNRS).
PY - 1978/9/15
Y1 - 1978/9/15
N2 - A series of Escherichia coli strains in which the lacZ gene is fused to any of the three maltose operons were previously isolated (Silhavy et al, 1976, 1977). Starting from one such strain, in which β-galactosidase synthesis is induced by maltose, mutants could be selected which synthesize this enzyme constitutively. Several of these mutants carry a mutation in malT, the positive regulator gene of the maltose system. The mutations, called malTc, are both cis and trans dominant over wild type. The failure of the malT+ product to repress the constitutive expression resulting either from a malTc mutation (this paper) or from initiator constitutive mutations (Hofnung & Schwartz 1971) strongly suggests that, in contrast to the l-arabinose system, the maltose system is regulated in a strictly positive manner.
AB - A series of Escherichia coli strains in which the lacZ gene is fused to any of the three maltose operons were previously isolated (Silhavy et al, 1976, 1977). Starting from one such strain, in which β-galactosidase synthesis is induced by maltose, mutants could be selected which synthesize this enzyme constitutively. Several of these mutants carry a mutation in malT, the positive regulator gene of the maltose system. The mutations, called malTc, are both cis and trans dominant over wild type. The failure of the malT+ product to repress the constitutive expression resulting either from a malTc mutation (this paper) or from initiator constitutive mutations (Hofnung & Schwartz 1971) strongly suggests that, in contrast to the l-arabinose system, the maltose system is regulated in a strictly positive manner.
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U2 - 10.1016/0022-2836(78)90304-2
DO - 10.1016/0022-2836(78)90304-2
M3 - Article
C2 - 101676
AN - SCOPUS:0018076641
SN - 0022-2836
VL - 124
SP - 359
EP - 371
JO - Journal of Molecular Biology
JF - Journal of Molecular Biology
IS - 2
ER -