EFFECT OF THE TEMPERATURE OF GROWTH OF ESCHERICHIA COLI ON THE FORMATION OF β-GALACTOSIDASE

Author:

Marr Allen G.1,Ingraham John L.1,Squires Craig L.1

Affiliation:

1. Department of Bacteriology, University of California, Davis, California

Abstract

Marr, Allen G. (University of California, Davis), John L. Ingraham, and Craig L. Squires . Effect of the temperature of growth of Escherichia coli on the formation of β-galactosidase. J. Bacteriol. 87: 356–362. 1964.—The synthesis of β-galactosidase was measured during exponential growth of Escherichia coli in a succinate-minimal medium over a temperature range of 10 to 43 C for the following: (i) a constitutive strain, and (ii) an inducible cryptic strain, induced maximally with isopropyl-thio-β- d -galactopyranoside (IPTG), or induced submaximally with IPTG. The differential rates of synthesis of β-galactosidase were identical for the constitutive strain and for the fully induced strain; the rates were constant from 20 to 43 C, and decreased progressively with a decrease in temperature below 20 C. Thus, in the absence of specific repression, the ability of E. coli to produce β-galactosidase decreases at low temperature. The differential rate of the submaximally induced culture was minimal between 20 and 30 C, and increased progressively with temperature both above 30 C and below 20 C. That the repressor concentration is maximal at 20 C was established by measuring the rate of induced synthesis of β-galactosidase as a function of the concentration of IPTG; the relative concentrations of repressor were 1.00:3.28:0.25 at 40, 20, and 10 C, respectively. After an abrupt change in temperature, the differential rate of a submaximally induced culture changed gradually to the rate of the steady state, which is in agreement with the proposal that the effect of temperature is on the concentration of repressor and not on the equilibrium between repressor and its site of action. The effect of temperature on catabolic repression was determined by comparing the differential rate of synthesis of β-galactosidase by a constitutive strain grown in succinate-minimal medium with the rate in glucose-minimal medium at various temperatures; the ratio of the rates in the two media decreased progressively and approached 2.0 as the temperature of growth was increased.

Publisher

American Society for Microbiology

Subject

Molecular Biology,Microbiology

Reference21 articles.

1. Kinetics studies of ,B-galactosidase induction;BOEZI J. A.;Biophys. J.,1961

2. Catabolite repression;BROWN;Cold Spring Harbor Symp. Quant. Biol.,1961

3. The effect of temperature on the nutritional requiremenit of facultative and obligate thermophilic hacteria;VAIPBELL L. L.;J. Bacteriol.,1953

4. CLARK 1). J. 1963. Catabolite repression of 0- galactosidase in Escherichia coli. Ph.D. Thesis IUniversity of California Davis.

5. Physiology of the inhibition by glucose of the induced synthesis of the f-galactosidase-enzyme system of Escherichia coli;COHN AI.;J. Bacteriol.,1959

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3