Pseudomonas-like bacteria

Yasumoto et al. (30) describe two components of a Pseudomonas sp. culture with identical HPLC retention times to TTX and anhydro-TTX. These fractions produced typical signs of TTX intoxication in mice, with median death times similar to standard TTX and anhydro-TTX. Noguchi et al. (32) demonstrate by HPLC and GC-MS analyses that 7 biotypes of Vibrio sp. produced substances with retention times and molecular weights similar to TTX and anhydro-TTX. However, they observed mouse toxicity in only 1 biotype. Likewise, Simidu et al. (34) report that extracts of V. alginolyticus ATCC 17749 cultures displayed TTX-like toxicity in mice. The latter study shows that a variety of marine bacteria, plus E. coliy produced substances that, by HPLC analysis, were identical to TTX and anhydro-TTX. 

Mainly [l,2,4]triazolo[3,4-3][l,3,4]thiadiazoles 139 have been tested for their activity against various bacteria like Escherichia coli, Staphylococcus aureus, Candida albicans, Pseudomonas aeruginosa, Klebsiella pneumoniae, or Bacillus subtillis (Table 4). 

Local treatment of skin and soft tissue infections with antibiotic-containing ointments or solutions should not be used because it leads to allergic reactions and rapid development of bacterial resistance. In settings where MRSA or resistant Enterobacte-riaceae (like ESBL s gram negative bacteria with extended spectrum beta lactames) or Pseudomonas spp. occur, the empiric use of vancomycin and a carbapenem can be necessary. The risk of transmission of these organisms should be minimalised by hygienic and isolation measures. 

Most slime-forming bacteria are aerobic. Species such as Pseudomonas produce an extracellular, gel-like, polysaccharide capsule which acts to protect and shield the organism. When in combination with other metabolic by-products, bacteria... 

It is formed by acylases that cleave off the side chain of the penicillins, and can also be obtained by the selective chemical cleavage of the amide, leaving the lactam intact. After this, 6-APA can be easily acylated by any carboxylic acid, and this has yielded literally thousands of semisynthetic penicillins in the past 30 years, many showing improved stability and activity. Some of them are lactamase resistant (methicillin (9.41), oxacillin (9.42) and its halogenated derivatives), whereas others are broad-spectrum antibiotics, like the orally active ampicillin (9.43), which also inhibits Gramnegative bacteria but is sensitive to lactamase. Carbenicillin (9.44) is particularly active against Pseudomonas and Proteus infections, which are unaffected by natural penicillins. Piperacillin (9.45), a broad-spectrum compound, is spectacularly active against Pseudomonas. 

Although the pathway of Eq. (1) is now based on much evidence (Section 111) and is unambiguous in the case of at least one bacterium [Pseudomonas stutzeri strain Zobell (f. sp. P. perfectomarina)], there have been alternative hypothesis. One hypothesis, advanced by the Hollocher group (Garber and Hollocher, 1981 St. John and Hollocher, 1977), considered NO as a likely intermediate, but one that remained at least partly enzyme-bound and was not entirely free to diffuse. This view was based on the outcome of certain kinetic and isotope experiments which can be summarized as follows. When denitrifying bacteria were challenged simultaneously with [ N]nitrite and ordinary NO, the cells reduced both compounds concomitantly to N2 (or to N2O in the presence of acetylene which is a specific inhibitor (Balderston et al., 1976 Yoshinari and Knowles, 1976) of nitrous oxide reductase). In the process, little NO was generally detected in the gas phase pool of NO and there was relatively little isotopically mixed N2O formed. That is, most of the N and N reduced to NjO appeared as N2O... 

Fungi (e.g. Cunninghamella sp., Aspergillus sp., Saccharomyces cerevisiae) are eukaryotic organisms, like mammals, and are the most commonly utilized microorganisms in biotransformation studies [31, 32]. The use of bacteria (prokaryotes) is limited mostly to actinomycetes that seem to contain an enzyme system very similar to that of fungi. Other bacteria (e.g. Pseudomonas, Escherichia coli) are used occasionally, but their usefulness is limited [26, 33]. 

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