Escherichia strain

Fig. 21.4 Fate of pyruvic acid in Escherichia strains. Involves a phosphoroclastic split of pyruvic acid in which inorganic phosphate and ADP give rise to ATP.

Certain strains of Escherichia coli can be stimulated by irradiation with a moderate dose of ultraviolet (UV) light to stop normal growth and start producing bacteriophages that eventually lyse the bacterium. Bacteria of these so-called lysogenic strains carry the DNA of the phage integrated into their own... 

Escherichia coli (E. coli) A species of bacteria that inhabits the intestinal tract of most vertebrates. Many non-pathogenic strains are used experimentally as hosts for rDNA. 

Human insulin is derived from a biosynthetic process using strains of Escherichia coli (recombinant DNA, rDNA). Human insulin appears to cause fewer allergic reactions than does insulin obtained from animal sources. Insulin analogy, insulin lispro, and insulin aspart are newer forms of human insulin made by using recombinant DNA technology and are structurally similar to human insulin. 

Escherichia coli K12 TGI strain was used as a recipient for transformation. At studying of SOS-system activity the recombinant bioluminescent strain of Escherichia coli recA lux containing plasmid-borne fusions of the recA promoter-operator region to the Photorhabdus luminescens ZM 1 lux genes (GosNlIgenetika, Russia) was used. Increase of their luminescence in the presence of DNA damage factors [Rosen et al., 2000], were shown previously. Investigation of the luminescent response of this strain to UV radiation allows quantitatively estimate in a real time a SOS-system induction. 

Recombinant resilin production was induced, with the nonmetabolizable lactose analogue IPTG, in the Escherichia coli bacterial strain BL21(DE3)/pLysS. Cells were collected by centrifugation (10,000 g, 20 min at 4°C) and the cell pellet frozen at 80°C. 

Restriction enzymes are named after the bacterium from which they are isolated. For example, EcoRI is from Escherichia coli, and BamEII is from Bacillus amyloliquefaciens (Table 40-2). The first three letters in the restriction enzyme name consist of the first letter of the genus (E) and the first two letters of the species (co). These may be followed by a strain designation (R) and a roman numeral (I) to indicate the order of discov-ery (eg, EcoRI, EcoRIE). Each enzyme recognizes and cleaves a specific double-stranded DNA sequence that is 4—7 bp long. These DNA cuts result in blunt ends (eg,... 

Bacteria which are almost always sensitive to the sulphonamides include Strep, pneumoniae, /3-haemolytic streptococci, Escherichia coli and Proteus mirabilis those almost always resistant include Enterococcus faecalis, Ps. aeruginosa, indole-positive Proteus and Klebsiella whereas bacteria showing a marked variation in response include Staph, aureus, gonococci, El. influenzae and hospital strains of E. coli and Pr. mirabilis. 

Azospmlhtm strains were grown on LB medium containing 1% (w/v) pectin at 30°C for seven days, and Escherichia coli transformants for two days. Culture media were centrifuged at 10.000 g for 10 minutes. The supernatant constituted the enzyme preparation. 

On solid medium, Azospirilhim and Escherichia coli strains were plated on LB agar with l%(w/v) pectin and after six days of incubation, the plates were overlayed with 2% (w/v) solution of hexadecyltrimetyl ammonium bromide (HTAB) (Plazinski and... 

From a genetical point of view, Saccharomyces cerevisiae is an ideal organism which may be considered the Escherichia coli of eukaryotic cells [4,5]. This is true in particular for the study of metabolic regulation and for that of membrane transport [6]. Finally, the astonishing resemblance between many yeast proteins and certain mammalian-cell proteins has seriously broadened the scope of interest. Although a few reports have appeared on amino acid transport in some other yeasts, most investigations in this field have used strains of Saccharomyces cerevisiae. 

A strain of Escherichia coli produces a naphthotriazole from 2,3-diaminonaphthalene and nitrite that is formed from nitrate by the action of nitrate reductase. The initial product is NO, which is converted by reactions with oxygen into the active nitrosylating agent that reacts chemically with the amine (Ji and Hollocher 1988). A comparable reaction may plausibly account for the formation of dimethylnitrosamine by Pseudomonas stutzeri during growth with dimethylamine in the presence of nitrite (Mills and Alexander 1976) (Figure 2.2f). 

Iwaki H, Y Hosegawa, S Wang, MM Kayser, PCK Lau (2002) Cloning and characterization of a gene cluster involved in cyclopentanol metabolism in Comamonas sp. strain NCIMB 9872 and biotransformations effected by Escherichia co/f-expressed cyclopentanone 1,2-monooxygenase. Appl Environ Microbiol 68 5671-5684. 

Wu J-F, C-W Sun, C-Y Jiang, Z-P Liu, S-J Liu (2005) A novel 2-aminophenol 1,6-dioxygenase involved in the degradation of p-chloronitrobenzene by Comamonas strain CNB-1 purification, properties, genetic cloning and expression in Escherichia coli. Arch Microbiol 183 1-8. 

Dimeric flavoprotein chromate reductases have been purified from Pseudomonas putida (ChrR) and Escherichia coli (YieF). The former produces a semiquinone and transiently reactive oxygen species, whereas the latter is an obligate four-electron reductant. One-electron reduction of Cr(Vl) to Cr(V) has, however, been observed as an intermediate in the reduction by the NAD(P)H-dependent reductase of Pseudomonas ambigua strain G-1 (Suzuki et al. 1992). 

The degradation of phenylmercuric acetate to benzene, methylmercuric chloride to methane, and ethylmercuric chloride to ethane and Hg + is apparently carried out by different enzymes from the plasmid-carrying Escherichia coli strain K12 (R831) (Schottel 1978) and Pseudomonas sp. Resistance to organic mercury compounds has also been found in clinical isolates of nontuber-culous, rapidly growing mycobacteria (Steingrube et al. 1991) and can present a challenge in the clinical environment. 

Schottel JL (1978) The mercuric and organomercurial detoxifying enzymes from a plasmid-bearing strain of Escherichia coli. J Biol Chem 253 4341-4349. 

A study with a strain of plasmid-bome antibiotic-resistant Escherichia coli indicated that the strain did not transmit these plasmids to indigenous strains after introduction into the terrestrial environment (Devanas et al. 1986). 

Devanas MA, D Rafaeli-Eshkol, G Stotsky (1986) Survival of plasmid-containg strains of Escherichia coli in soil effect of plasmid size and nutrients on survival of hosts and maintenance of plasmids. Curr Microbiol 13 269-277. 

Mondello FJ (1989) Cloning and expression in Escherichia coli of Pseudomonas strain LB400 genes encoding polychlorinated biphenyl degradation. J Bacteriol 171 1725-1732. 

Advances in molecular biology have led to the construction of strains that include the relevant degradative genes. Amplihcation of these, and expression of them in Escherichia coli has made possible the isolation of pure enzymes in quantities suitable for crystallization. 

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