Pseudomonas enzyme action

Nashif, S. A. and Nelson, F. E. 1953C. The lipase of Pseudomonas fragi. III. Enzyme action in cream and butter. J. Dairy Sci. 36, 481-488. 

Formed by oxidative enzymic action of Pseudomonas graveolens on maltose. Used as an additive in instant food preparations. Mg +98.3 (H2O). 

However, whatever the mechanism of action is, the effect of solvents on enzyme selectivity is sometimes really dramatic. For example, Hrrose et al. [42] reported that in the Pseudomonas species lipase-catalyzed desymmetrization of prochiral... 

The anti-Pseudomonas action of norfloxacin is related to its ability to inhibit chromosome duplication in rapidly-dividing cells. Which of the following enzymes participates in bacterial DNA replication and is directly inhibited by this antibiotic ... 

Efforts to overcome the actions of the p-lactamases have led to the development of such p-lactamase inhibitors as clavulanic acid, sulbactam, and tazobactam. They are called suicide inhibitors because they permanently bind when they inactivate p-lactamases. Among the p-lactamase inhibitors, only clavulanic acid is available for oral use. Chemical inhibition of p-lactamases, however, is not a permanent solution to antibiotic resistance, since some p-lactamases are resistant to clavulanic acid, tazobactam, or sulbactam. Enzymes resistant to clavulanic acid include the cephalosporinases produced by Citrobacter spp., Enterobacter spp., and Pseudomonas aeruginosa. 

These substances resemble 3-lactam molecules (Figure 43-7) but they have very weak antibacterial action. They are potent inhibitors of many but not all bacterial 3 lactamases and can protect hydrolyzable penicillins from inactivation by these enzymes. -Lactamase inhibitors are most active against Ambler class A lactamases (plasmid-encoded transposable element [ ] lactamases in particular), such as those produced by staphylococci, H influenzae, N gonorrhoeae, salmonella, shigella, E coli, and pneumoniae. They are not good inhibitors of class lactamases, which typically are chromosomally encoded and inducible, produced by enterobacter, citrobacter, serratia, and pseudomonas, but they do inhibit chromosomal 3 lactamases of bacteroides and moraxella. 

Later it was found that other monoses could be exchanged directly for D-fructose in the sucrose molecule. First, sucrose labelled with C14 in the D-fructose portion was prepared by the action of the Pseudomonas sac-charophila enzyme on ordinary sucrose and C14 labelled D-fructose.44 Subsequently D-fructose has been exchanged in the same manner for other monoses, for example, L-sorbose.48 Thus new oligosaccharides may be prepared by exchanging one monose for another through the action of this enzyme without the use of the phosphate intermediate. 

Deracemization of mandelic add with the combined action of two enzymes has been reported. rac-MandeUc acid is acylated by a Pseudomonas sp. lipase in diisopropyl ether. After solvent removal the mfacture of mandeUc acid enriched in the R-form and the 0-acetyl derivative of the S-configuration are subjected to the mandelate racemase-catalyzed racemization in aqueous buffer. In these conditions only the non-acetylated hydroxy acid is racemized. In order to obtain (S)-0-acetylmandelic acid in an 80% isolated yield and a >98% e.e. the process must be repeated four times [9]. 

Enzyme inhibitors such as cloxacillin and methicillin have been shown to potentiate the action of certain penicillins and cephalosporins against Ps. aeruginosa Figure 7.7). Thus, the presence of cloxacillin, which is a strong inhibitor of the inducible enzyme, potentiates the effect of cephaloridine which alone is susceptible to hydrolysis by the pseudomonas lactamase. Cloxacillin shows no antibacterial activity against... 

The other enantiomer was left untouched by Pseudomonas cepacia lipase (PCL), the enzyme of choice. After reaction is complete, the resolved alcohol must be separated from its enantiomeric acetate 41. It is noteworthy that the enzyme functions in a buffered aqueous acetone medium acetone does not interfere with the action of the enzyme. 

Other possibilities to prepare chiral cyanohydrins are the enzyme catalysed kinetic resolution of racemic cyanohydrins or cyanohydrin esters [107 and references therein], the stereospecific enzymatic esterification with vinyl acetate [108-111] (Scheme 2) and transesterification reactions with long chain alcohols [107,112]. Many reports describe the use of fipases in this area. Although the action of whole microorganisms in cyanohydrin resolution has been described [110-116],better results can be obtained by the use of isolated enzymes. Lipases from Pseudomonas sp. [107,117-119], Bacillus coagulans [110, 111], Candida cylindracea [112,119,120] as well as lipase AY [120], Lipase PS [120] and the mammalian porcine pancreatic lipase [112, 120] are known to catalyse such resolution reactions. 

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