Pseudomonas specificities

Class V enzymes have a penicillinase profile, including activity against cloxacillin they are resistant to inhibition by p-chloromercuribenzoate.This class of enzymes includes the oxacillin-hydrolysing enzymes, OXA-1, OXA-2, and OXA-3, and the Pseudomonas-specific carbenicillin hydrolysing enzymes, PSE-1, PSE-2, PSE-3, and PSE-4. They are plasmid-mediated enzymes and are found in E. coli. Pseudomonas and Serratia species. 

TEM enzymes were named after a young girl named Temoniera, from whom they were first isolated [13] SHV enzymes are sulphydryl variable HMS enzymes were named after Hedges, Matthew and Smith OXA enzymes are so named as they are oxacillin-hydrolyzing PSE enzymes are Pseudomonas specific enzymes. 

Specific bacteriostatic activity against Escherichia coli (681, 896, 899), Staphylococcus aureus (681, 896), Cocci (900), Shigella dysenteriae (681), Salmonella ryphi (681), Proteus vulgaris (681), Pseudomonas aeruginosa (681), Streptococcus (889, 901, 902) and Pneumococcus (901-904). 

In this process, penicillin G is first hydrolysed to 6-APA with the acylase derived from Kluyvera citwphila at a slightly alkaline pH (pH 75). Subsequently the 6-APA is incubated with an acylase derived from Pseudomonas mdanogenum and with DL-phenylglydne methyl ester at pH 55. This produces ampiciilin in reasonable yields only because of the specificity of the P. melanogenum enzyme. This enzyme does not react with penicillin G nor phenylacetic acid. 

Specific information about the optimum conditions for the synthesis and the activity of the enzyme has been reported for Pseudomonas fluorescens screening of various micro-organisms resulted in the selection of a P. fluorescens strain with an initial rate of conversion of 3 g P h 1 in an imoptimised state. The following conclusions could be made concerning the production of L-phenylalanine by P. fluorescens ... 

The 2-keto-3-deoxy-aldonic acid (phosphate) aldolases from Pseudomonas strains - 3-deoxy-2-keto-L-arabonate (F.C 4.1.2.18), 3-deoxy-2-keto-D-xylonate (EC 4.1.2.28), 3-deoxy-2-keto-6-phospho-D-gluconate (EC 4.1.2.14) and 3-deoxy-2-keto-6-phospho-D-galactonate aldolase (EC 4.1.2.21) - appear to be specific even for the acceptor components, but allow stereoselective syntheses of the respective natural substrates29. 

Wang et al.2 and Najafpour et al.3A worked with immobilised microbial cells of Nitrobacer agilis, Saccharomyces cerevisiae and Pseudomonas aeruginosa in gel beads, respectively. They found separately that the cells retained more than 90% of their activity after immobilisation by using specific oxygen uptake rate (SOUR) [mg 02g 1 (dry biomass) h 11 as the biomass activity indicator. Such differences in immobilised biomass and activity between free and immobilised biomass activities depend strongly on the particular characteristics of the microbial systems and their interaction with the support matrix. 

In several polysaccharides containing glycuronic acid residues, the carboxyl groups of these are linked to the amino group of amino compounds, forming amides. In the simplest examples, these are primary amides, such as the 2-formamido- and 2-acetamido-2-deoxy-D-galacturonamide (49) residues in 0-specific polysaccharides from different strains of Pseudomonas... 

If common marine bacteria, such as Vibrio sp. and Pseudomonas sp., indeed produce TTXs, it might be expected that more animals, particularly those living in aquatic environments, would be toxic. However, apparently only specific animals can concentrate TTX and/or provide a niche for TTX-producing bacteria. 

The mechanism of acquired resistance in Pseudomonas aeruginosa is different. Chromosomal mutations result in the increase of a specific outer membrane protein with a concomitant reduction in divalent cations. Polymyxins bind to the outer membrane at sites normally occupied by divalent cations, and therefore it is thought that a reduction in these sites will lead to decreased binding of the antibiotic with a consequent decreased susceptibility of the cell. 

Examples of preservatives are phenylmercuric nitrate or acetate (0.002% w/v), chlorhexidine acetate (0.01 % w/v), thiomersal (0.01 % w/v) and benzalkorrium chloride (0.01 % w/v). Chlorocresol is too toxic to the comeal epithehum, but 8-hydroxyquinoline and thiomersal may be used in specific instances. The principal considerahon in relation to antimicrobial properties is the activity of the bactericide against Pseudomonas aeruginosa, a major source of serious nosocomial eye infections. Although benzal-konium chloride is probably the most active of the recommended preservatives, it cannot always be used because of its incompatibility with many compounds commonly used to treat eye diseases, nor should it be used to preserve eye-drops containing anaesthetics. Since benzalkonium chloride reacts with natural mbber, silicone or butyl rabber teats should be substituted. Since silicone mbber is permeable to water vapour, products should not be stored for more than 3 months after manufacture. As with all mbber components, the mbber teat should be pre-equilibrated with the preservative prior to... 

The 4-methoxybenzoate monooxygenase from Pseudomonas putida shows low substrate specificity. Although it introduces only a single atom of oxygen into 3-hydroxy- and 4-hydroxybenzoate, it accomplishes the conversion of 4-vinylbenzoate into the corresponding side-chain diol (Wende et al. 1989). 

Schleissner C, ER Olivera, M Eernandez-Valverde, M Luengo (1994) Aerobic catabolism of phenylacetic acid in Pseudomonas putida U biochemical characterization of a specific phenylacetic acid transport system and formal demonstration that phenylacetyl-coenzyme A is a catabolic intermediate. J Bacterial 176 7667-7676. 

Morawaski B, G Casy, C Illaszewicz, H Griengl, DW Ribbons (1997) Stereochemical course of two arene-cw-diol degydrogenases specifically induced in Pseudomonas putida. J Bacterial 179 4023-4029. 

Jones KH, RT Smith, PW Trudgill (1993) Diketocamphane enantiomer-specific Bayer-Villiger monooxygenases from camphor-grown Pseudomonas putida ATCC 17453. J Gen Microbiol 139 797-805. 

Larkin Ml (1988) The specificity of 1-naphthol oxygenases from three bacterial isolates, Pseudomonas spp. (NCIB 12042 and 12043) and Rhodococcus sp. (NCIB 12038) isolated from garden soil. EEMS Microbiol Lett 52 173-176. 

Bottiglieri M, C Keel (2006) Characterization of PhlG, a hydrolase that specifically degrades the antifungal compound diacetylphloroglucinol in the biocontrol agent Pseudomonas fluorescens CHAO. Appl Environ Microbiol 72 418-427. 

Substrate Specificity of 4-Chlorophenylacetate 3,4-Dioxygenase in Component A of Pseudomonas sp. Strain CBS (Markus et al. 1986)... 

Kaschabek SR, W Reineke (1995) Maleylacetate reductase of Pseudomonas sp. strain B13 specificity of substrate conversion and halide elimination. J Bacterial 177 320-325. 

Tomasi I, I Artaud, Y Bertheau, D Mansuy (1995) Metabolism of polychlorinated phenols by Pseudomonas cepacia ACllOO determination of the first two steps and specific inhibitory effect of methimazole. J Bacterial 111 307-311. 

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