Beta-galactosidase and selective neutrality
نویسندگان
چکیده
منابع مشابه
Selective Neutrality
Many enzymes in intermediary metabolism manifest saturation kinetics in which flux is a concave function of enzyme activity and often of the MichaelisMenten form. The result is that, when natural selection favors increased enzyme activity so as to maximize flux, a point of diminishing returns will be attained in which any increase in flux results in a disproportionately small increase in fitnes...
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HARTL, DYKHUIZEN and DEAN (1985) have recently proposed a hypothesis for the evolution of selective neutrality. Their idea is largely based on the metabolic models of KACSER and BURNS (1973, 1979, 1981), which show that flux through a metabolic pathway will typically be a concave function of the participating enzyme activities. HARTL and co-workers suggest that, where natural selection favors m...
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A gene encoding a third alpha-galactosidase (AglB) from Aspergillus niger has been cloned and sequenced. The gene consists of an open reading frame of 1,750 bp containing six introns. The gene encodes a protein of 443 amino acids which contains a eukaryotic signal sequence of 16 amino acids and seven putative N-glycosylation sites. The mature protein has a calculated molecular mass of 48,835 Da...
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Rohlfing, S. R. (Western Reserve University, Cleveland, Ohio), and I. P. Crawford. Purification and characterization of the beta-galactosidase of Aeromonas formicans. J. Bacteriol. 91:1085-1097. 1966.-The beta-galactosidase of Aeromonas formicans was purified by diethylaminoethyl cellulose chromatography and gel filtration on Sephadex G-200. The properties of the enzyme molecule were compared w...
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p-Galactosidase hydrolyzes p-n-galactosides, a-L-arabinosides, lactose, and heptosides with a P-n-galactose configuration (1). It occurs with fi-glucosidase in certain plants, bacteria, molds, and in mammalian tissues. It occurs without p-glucosidase in seeds of alfalfa and coffee, soy beans, and different strains of bacteria (Laclobacillus delbrueckii, Escherichia coli) (1). Enzymatic activity...
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ژورنال
عنوان ژورنال: Science
سال: 1979
ISSN: 0036-8075,1095-9203
DOI: 10.1126/science.113875