Molecular basis of beta-galactosidase alpha-complementation.
نویسندگان
چکیده
منابع مشابه
High resolution refinement of beta-galactosidase in a new crystal form reveals multiple metal-binding sites and provides a structural basis for alpha-complementation.
The unrefined fold of Escherichia coli beta-galactosidase based on a monoclinic crystal form with four independent tetramers has been reported previously. Here, we describe a new, orthorhombic form with one tetramer per asymmetric unit that has permitted refinement of the structure at 1.7 A resolution. This high-resolution analysis has confirmed the original description of the structure and rev...
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Bacillus stearothermophilus IAM11001 produced three beta-galactosidases, beta-galactosidase I, II, and III (beta-gal I, II, and III), which are detectable by polyacrylamide (nondenatured) gel electrophoresis. By connecting restriction fragments of the chromosomal DNA to plasmid vectors, followed by transformation of Escherichia coli, two beta-galactosidase genes (bgaA and bgaB) located close to...
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The characterization of protein interactions is important to the understanding of signal transduction pathways and cellular processes. Here we describe a method utilizing β-galactosidase (βgal) complementation that can monitor protein interactions in live mammalian cells (Rossi et al. 1997, 2000; Blakely et al. 2000). In brief, the method involves expressing chimeric proteins consisting of two ...
متن کاملStructural basis for the altered activity of Gly794 variants of Escherichia coli beta-galactosidase.
The open-closed conformational switch in the active site of Escherichia coli beta-galactosidase was studied by X-ray crystallography and enzyme kinetics. Replacement of Gly794 by alanine causes the apoenzyme to adopt the closed rather than the open conformation. Binding of the competitive inhibitor isopropyl thio-beta-D-galactoside (IPTG) requires the mutant enzyme to adopt its less favored ope...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 1975
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.72.4.1254