Escherichia coli 3-galactosidase

Geller AI, Breakefield XO (1988) A defective HSV-1 vector expresses Escherichia coli (3-galactosidase in cultured peripheral neurons. Science 241 1667-1669. 

Escherichia coli (3-galactosidase D-gij/<7rfo-Octenitol J3TI 32... 

Beale, E. G., Deeb, E. A., Handley, R. S., Akhavan-Tafti, H., and Schaap, A. P., A rapid and simple chemiluminescent assay for Escherichia coli -galactosidase. BioTechniques 12,320-323 (1992). 

The fact that ) -D-galactosidase from Escherichia coli is inactivated more rapidly in the absence of Mg than in its presence can be taken as evidence that the activation of the triazene 38, that is, formation of )5-D-galactosyl-methyldiazonium ion, proceeds without acid catalysis, because Mg is required for the proton-assisted catalysis of yS-D-galactoside hydrolysis by this enzyme.Additional evidence for the absence of acid catalysis in the de-... 

Clemmit, R.H. and Chase, H.A., Immobilized metal affinity chromatography of P-galactosidase from unclarified Escherichia coli homogenates using expanded bed adsorption, /. Chromatogr. A, 874, 27, 2000. 

Commercially available P-gal usually is isolated from Escherichia coli and has a pH optimum at 1-1.5. By contrast, mammalian p-galactosidases usually have a pH optimum within the range of 5.5-6 thus, interference from endogenous P-gal during immunohistochemical staining can be avoided. 

Hamaguchi, Y., Yoshitake, S., Ishikawa, E., Endo, Y., and Ohtaki, S. (1979) Improved procedure for the conjugation of rabbit IgG and Fab antibodies with b-D-galactosidase from Escherichia coli using N,N -o-phenylenedimaleimide. J. Biochem. (Tokyo) 85, 1289-1300. 

Detection of one molecule of P-D-galactosidase produced from Escherichia coli 152 Bovine serum albumin increases initial light intensity and eliminates the ad- 153... 

Escherichia coli cells grown in a medium with lactose as the only carbon source are monitored for p-galactosidase activity over time with the results shown below. 

Toxi-Chromotest is a commercial toxicity assay that is based on the assessment of the inhibition of (3-galactosidase activity, measured using a chromogenic substrate and a colorimeter. A mutant strain of Escherichia coli is revitalized from a lyophilized state prior to the test [39]. The principle of the MetSoil test is similar to that of the Toxi-Chromotest . 

The MetPAD test kit (Group 206 Technologies, Gainesville, Florida) has been developed for the detection of heavy metal toxicity. It has been used to determine the toxicity of sewage water and sludge, sediments, and soil [41]. The test is based on the inhibition of (3-galactosidase activity in an Escherichia coli mutant strain. Performance of the test does not require expensive equipment and it is therefore easily applied as a field test. 

B. W. Bainbridge, N. Mathias, R. G. Price, A. C. Richardson, J. Sandhu, and B. V. Smith, Improved methods for the detection of P-galactosidase activity in colonies of Escherichia coli using a new chromogenic substrate VBzTM-gal (2-[2-(4-P-D-galactopyranosyl-3-methoxyphenyl)-vinyl]-3-methyl-benzothiazolium toluene- 4-sulphonate), FEMS Microbiol. Lett., 80 (1991) 319-324. 

J. D. McCarter, M. J. Adam, and S. G. Withers, Binding energy and catalysis. Fluorinated and deoxygen-ated glycosides as mechanistic probes of Escherichia coli (lac Z) p-galactosidase, Biochem. J., 286 (1992) 721-727. 

M. L. Sinnot and P. J. Smith, Affinity labelling with deaminatively generated carbonium ion. Kinetics and stoicheiometry of die alkylation of methionine-500 of die lacZ p-galactosidase of Escherichia coli by p-D-galactopyranosylmethyl-p-nitrophenyltriazene, Biochem. J., 175 (1978) 525—538. 

J. Langridge, Mutations conferring quantitative and qualitative increases in P-galactosidase activity in Escherichia coli, Mol. Gen. Genet., 105 (1969) 74-83. 

S. Yoon, H.G. Kim, K.H. Chun, J.E.N. Shin, 4-deoxy-analogs of p-nitrophenyl /i-D-galactopyranosides for specificity study with /J-galactosidase from escherichia coli. Bull. Korean Chem. Soc. 17 (1996) 599-604. 

J.P. Richard, J.G. Westerfeld, S. Lin, Structure-reactivity relationships for beta-galactosidase (Escherichia coli, lac Z). 1. Bronsted parameters for cleavage of alkyl beta-D-galactopyranosides, Biochemistry 34 (1995) 11703-11712. 

Isolation of alkaline phosphatase from Escherichia coli in which 85% of the proline residues were replaced by 3,4-dehydro-proline affected the heat lability and ultraviolet spectrum of the protein but the important criteria of catalytic function such as the and were unaltered (12). Massive replacement of methionine by selenomethionine in the 0-galactosidase of E. coli also failed to influence the catalytic activity. Canavanine facilely replaced arginine in the alkaline phosphatase of this bacterium at least 13 and perhaps 20 to 22 arginyl residues were substituted. This replacement by canavanine caused subunit accumulation since the altered subunits did not dimerize to yield the active enzyme (21). Nevertheless, these workers stated "There was also formed, however, a significant amount of enzymatically active protein in which most arginine residues had been replaced by canavanine." An earlier study in which either 7-azatryptophan or tryptazan replaced tryptophan resulted in active protein comparable to the native enzyme (14). 

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