Membrane bound and soluble adenosine triphosphatase of Escherichia coli K 12. kinetic properties of the basal and trypsin-stimulated activities

1975 ◽  
Vol 9 (2) ◽  
pp. 85-95 ◽  
Author(s):  
José Carreira ◽  
Emilio Muñoz
Keyword(s):  
Escherichia Coli ◽  
Adenosine Triphosphatase ◽  
Kinetic Properties ◽  
Membrane Bound ◽  
K 12

scholarly journals Characterization of cuckoo-pint (Arum maculatum) mitochondrial adenosine triphosphatases

1986 ◽  
Vol 233 (3) ◽  
pp. 839-844 ◽  
Author(s):  
P P J Dunn ◽  
A R Slabas ◽  
A L Moore
Keyword(s):  
Adenosine Triphosphatase ◽  
Kinetic Properties ◽  
Ph Profile ◽  
Enzyme Preparations ◽  
Adenosine Triphosphatases ◽  
Membrane Bound ◽  
Cold Stability ◽  
Arum Maculatum ◽  
Guanosine Triphosphatase ◽  
Soluble Enzymes

The catalytic properties of cuckoo-pint (Arum maculatum) mitochondrial adenosine triphosphatase have been analysed. The pH profile, effect of inhibitors, cold-stability and substrate specificity are characteristic of mitochondrial adenosine triphosphatases, although a high guanosine triphosphatase activity does appear to be restricted to plant mitochondrial adenosine triphosphatases. The kinetic properties of nucleoside 5′-triphosphate hydrolysis by membrane-bound and soluble enzymes have been studied by means of double-reciprocal plots. These plots were linear in the absence of an activating anion, which may indicate that the catalytic and/or regulatory mechanism of Arum maculatum adenosine triphosphatase is different from that of other enzyme preparations. It is suggested that the differences in subunit composition of plant and mammalian adenosine triphosphatases reported previously [Dunn, Slabas & Moore (1985) Biochem. J. 225, 821-824] are structurally, rather than functionally, significant.

scholarly journals Glucose Transporter Mutants of Escherichia coli K-12 with Changes in Substrate Recognition of IICBGlc and Induction Behavior of theptsG Gene

2000 ◽  
Vol 182 (16) ◽  
pp. 4443-4452 ◽  
Author(s):  
Tim Zeppenfeld ◽  
Christina Larisch ◽  
Joseph W. Lengeler ◽  
Knut Jahreis
Keyword(s):  
Escherichia Coli ◽  
Glucose Transporter ◽  
Regulatory Mechanism ◽  
Single Copy ◽  
Amino Acid Residues ◽  
Inducer Exclusion ◽  
Membrane Bound ◽  
Dominance Tests ◽  
K 12 ◽  
Enzyme I

ABSTRACT In Escherichia coli K-12, the major glucose transporter with a central role in carbon catabolite repression and in inducer exclusion is the phosphoenolpyruvate-dependent glucose:phosphotransferase system (PTS). Its membrane-bound subunit, IICBGlc, is encoded by the gene ptsG; its soluble domain, IIAGlc, is encoded by crr, which is a member of the pts operon. The system is inducible by d-glucose and, to a lesser degree, byl-sorbose. The regulation of ptsG transcription was analyzed by testing the induction of IICBGlctransporter activity and of a single-copy Φ(ptsGop-lacZ) fusion. Among mutations found to affect directly ptsGexpression were those altering the activity of adenylate cyclase (cyaA), the repressor DgsA (dgsA; also called Mlc), the general PTS proteins enzyme I (ptsI) and histidine carrier protein HPr (ptsH), and the IIAGlc and IIBGlc domains, as well as several authentic and newly isolated UmgC mutations. The latter, originally thought to map in the repressor gene umgC outside theptsG locus, were found to represent ptsGalleles. These affected invariably the substrate specificity of the IICBGlc domain, thus allowing efficient transport and phosphorylation of substrates normally transported very poorly or not at all by this PTS. Simultaneously, all of these substrates became inducers for ptsG. From the analysis of the mutants, fromcis-trans dominance tests, and from the identification of the amino acid residues mutated in the UmgC mutants, a new regulatory mechanism involved in ptsG induction is postulated. According to this model, the phosphorylation state of IIBGlc modulates IICGlc which, directly or indirectly, controls the repressor DgsA and hence ptsGexpression. By the same mechanism, glucose uptake and phosphorylation also control the expression of the pts operon and probably of all operons controlled by the repressor DgsA.

Membrane-Bound Adenosine Triphosphatase of Escherichia coli

1977 ◽  
Vol 81 (4) ◽  
pp. 1071-1077 ◽  
Author(s):  
Hiroshi KOBAYASHI ◽  
Masatomo MAEDA ◽  
Yasuhiro ANRAKU
Keyword(s):  
Escherichia Coli ◽  
Adenosine Triphosphatase ◽  
Membrane Bound

scholarly journals Physiological and morphological effects of overproduction of membrane-bound ATP synthase in Escherichia coli K-12.

1984 ◽  
Vol 3 (8) ◽  
pp. 1791-1797 ◽  
Author(s):  
K. von Meyenburg ◽  
B.B. Jørgensen ◽  
B. van Deurs
Keyword(s):  
Escherichia Coli ◽  
Atp Synthase ◽  
Membrane Bound ◽  
K 12

scholarly journals Isolation and Characterization of Tributyltin Resistant Mutants of Escherichia coli

1984 ◽  
Vol 39 (3-4) ◽  
pp. 293-299 ◽  
Author(s):  
Akhand P. Singh ◽  
Kiran Singh
Keyword(s):  
Escherichia Coli ◽  
Class Ii ◽  
Class I ◽  
Isolation And Characterization ◽  
Membrane Bound ◽  
Resistant Mutants ◽  
K 12 ◽  
Spontaneous Mutants ◽  
Wild Type Parent

Two classes of tributyltin (TBT) resistant, spontaneous mutants of Escherichia coli K-12 were isolated, using a cytochrome containing (W 1485) and a cytochrome deficient (SASX76) strain. In contrast to the cytochrome sufficient strain, the cytochrome deficient strain was found to be fifty times more sensitive to TBT. The class I mutants, isolated from strain W 1485, also showed crossresistance to triphenyltin (TPT). As compared to its wild type parent, the TBT-resistant mutants exhibited mucoid colony type, aberrant cell morphology and reduced uptake of TPT. Based on these results, it was suggested that the resistance of class I mutants to TBT may be associated with above mentioned alterations. The class II TBT-resistant mutants were isolated from the cytochrome deficient strain, SASX76. In comparison to class I mutants, these class II mutants were found to have TBT-resistant membrane bound adenosine triphosphatase (ATPase) which may account for their resistance to TBT

scholarly journals Oxidative phosphorylation in Escherichia coli K12. An uncoupled mutant with altered membrane structure

1974 ◽  
Vol 138 (2) ◽  
pp. 211-215 ◽  
Author(s):  
G. B. Cox ◽  
F. Gibson ◽  
L. McCann
Keyword(s):  
Escherichia Coli ◽  
Electron Transport ◽  
Membrane Structure ◽  
Mutant Allele ◽  
Adenosine Triphosphatase ◽  
Mineral Salts ◽  
Normal Cells ◽  
E Coli ◽  
Escherichia Coli K12 ◽  
Membrane Bound

1. A new mutant strain (AN228) of Escherichia coli K12, unable to couple phosphorylation to electron transport, has been isolated. The mutant allele (unc-405), in strain AN228, was found to map near the uncA and uncB genes at about minute 74 on the E. coli genome. 2. A transductant strain (AN285) carrying the unc-405 allele is similar to the uncA and uncB mutants described previously in that it is unable to grow on succinate, gives a low aerobic yield on limiting concentrations of glucose, has a normal rate of electron transport, is unable to couple phosphorylation to electron transport, and lacks ATP-dependent transhydrogenase activity. 3. Strain AN285 (unc-405) is similar to an uncA mutant, but different from an uncB mutant, in that it is unable to grow anaerobically in a glucose–mineral-salts medium, and membrane preparations do not have Mg2+-stimulated adenosine triphosphatase activity. 4. Strain AN285 (unc-405) does not form an aggregate analogous to the membrane-bound Mg2+-stimulated adenosine triphosphatase aggregate found in normal cells. In this respect it differs from strain AN249 (uncA−), which forms an inactive membrane-bound Mg2+-stimulated adenosine triphosphatase aggregate.

KINETICS OF THREONINE DEAMINASE OF ESCHERICHIA COLI K-12 AND A STREPTOMYCIN-DEPENDENT MUTANT

1967 ◽  
Vol 45 (1) ◽  
pp. 1-10 ◽  
Author(s):  
I. D. Desai ◽  
W. J. Polglase
Keyword(s):  
Escherichia Coli ◽  
Selective Advantage ◽  
Kinetic Properties ◽  
Wild Type ◽  
Threonine Deaminase ◽  
E Coli ◽  
Type K ◽  
Hyperbolic Curve ◽  
K 12 ◽  
Kinetics Of

The relation between threonine deaminase activity and threonine concentration in sonic extracts of wild-type and streptomycin-dependent Escherichia coli K-12 was found to follow a hyperbolic curve. A similar relationship was obtained between enzyme activity and pyridoxal concentration. However, when serine was used as substrate, the activity–concentration curve was sigmoid, suggesting that serine may be a weaker effector of allosteric transition than threonine. The kinetic properties of the (derepressed) threonine deaminase of streptomycin-dependent E. coli K-12 were found to be similar to those of the enzyme of the wild-type K-12.It is postulated that derepression of threonine deaminase in streptomycin-dependent E. coli K-12 provides a selective advantage which permits exponential growth of this mutant in the presence of L-valine, which is an excretory product of streptomycin-dependent microorganisms.

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