Other bacteria

Although Brevundimonas (Pseudomonas) diminuta (ATCC 19146) is most commonly used for steriliziug-grade filter vaUdation, iu certain appHcations other bacteria are used. For example, when it is necessary to demonstrate removal of mycoplasma in appHcations involving sera and tissue culture media, membranes having a smaller pore size rating, eg, 0.1 p.m, are frequentiy used. For these membranes,laidlawii may be employed for vaHdation purposes (9). 

Tuberculocidal Test. The tubercle bacillus is resistant to disinfectants because the cells are protected with a waxy coating that is not readily penetrated. The tuberculocidal test is a use dilution practical type test that employs porcelain cylinders. The bacteria are different from those in the use dilution method (Table 10), the incubation time is longer, and the details of the procedure are different. For example, in the tuberculocidal test the test is divided into two parts, a presumptive test and a confirmatory test. The former employs Mycobacterium smegmatis and the latter employs Mycobacterium bovis (BCG). For the presumptive test the incubation time is 12 days, as against 48 hours for other bacteria used in the use-dilution method. For the confirmatory test the incubation time is 60 days, with an additional 30 days in case there is no growth. As shown in Table 10, the concentrations of the phenol standard are higher than used with other bacteria. 

Commercial Alcoholic beverages Sauerkraut Pickles Cheeses Lactic acid Various yeasts, molds, and bacteria L. plantatum plus other bacteria L. plantaixim plus other bacteria Propionibacteria, molds, and possibly many other microorganisms Two lactobacillus species... 

The main agents of these losses are the microbes and small animals, such as springtails and mites, that inhabit the soil. These feed on organic matter that contains carbon and nitrogen and produce carbon dioxide and ammonium ions as waste products. Other bacteria convert the ammonium to nitrate. Like most of us, these organisms are most active when the conditions suit them best, and their preferred options are warmth and moisture. In early autumn, the soil is still warm... 

Bacteria are smaller than protozoa and are responsible for many diseases, such as typhoid fever, cholera, diarrhea, and dysentery. Pathogenic bacteria range in size from 0.2 to 0.6 /tm, and a 0.2 /tm filter is necessary to prevent transmission. Contamination of water supplies by bacteria is blamed for the cholera epidemics, which devastate undeveloped countries from time to time. Even in the U.S., E. coli is frequently found to contaminated water supplies. Fortunately, E. coli is relatively harmless as pathogens go, and the problem isn t so much with E. coli found, but the fear that other bacteria may have contaminated the water as well. Never the less, dehydration from diarrhea caused by E. coli has resulted in fatalities. 

Legionella pneumophila (LD) Infections, particularly pneumonia, caused by inhaling Legionella pneumophila and other bacteria from the family Legionel-laceas in water droplets drifting from cooling towers, showers, etc. 

The gradients of H, Na, and other cations and anions established by ATPases and other energy sources can be used for secondary active transport of various substrates. The best-understood systems use Na or gradients to transport amino acids and sugars in certain cells. Many of these systems operate as symports, with the ion and the transported amino acid or sugar moving in the same direction (that is, into the cell). In antiport processes, the ion and the other transported species move in opposite directions. (For example, the anion transporter of erythrocytes is an antiport.) Proton symport proteins are used by E. coU and other bacteria to accumulate lactose, arabinose, ribose, and a variety of amino acids. E. coli also possesses Na -symport systems for melibiose as well as for glutamate and other amino acids. 

The great evaporite basin deposits of elemental sulfur in Poland were discovered only in 1953 but have since had a dramatic impact on the economy of that country which, by 1985, was one of the world s leading producers (p. 649). The sulfur occurs in association with secondary limestone, gypsum and anhydrite, and is believed Ui be derived from hydrocarbon reduction of sulfates assisted 1 bacterial action. The H2S so formed is consumed by other bacteria to produce sulfur as waste — this accumulates in the bodies of the bacteria until death, when the sulfur remains. 

Other bacteria, those that do not have light available to diem, couple die reaction... 

Other bacteria such as E. coli assimilate ammonia by incorporating it directly into a-oxoglutarate in a reaction catalysed by glutamate dehydrogenase (GDH). This reaction can be written as... 

The chromosomes of Escherichia coli and other bacteria are single, double-stranded DNA molecules with a total length of more than 1,000 pm. Relaxed DNA exists as a helical molecule, with one full turn of the helix occurring approximately every 10.4 base pairs. This molecule must undergo several folding and compaction steps to fit into an E. coli cell which is only 1-3 pm long. Despite this enormous compaction, bacterial DNA must be accessible for the bacterial enzymes that catalize DNA replication and transcription... 

In summary, it appears that the protein has to adopt the correct fold before the Rieske cluster can be inserted. The correct folding will depend on the stability of the protein the Rieske protein from the thermoacidophilic archaebacterium Sulfolobus seems to be more stable than Rieske proteins from other bacteria so that the Rieske cluster can be inserted into the soluble form of the protein during expression with the help of the chaperonins. If the protein cannot adopt the correct fold, the result will be either no cluster or a distorted iron sulfur cluster, perhaps using the two cysteines that form the disulfide bridge in correctly assembled Rieske proteins. 

Bacterial resistance to antibiotics has been recognized since the first drugs were introduced for clinical use. The sulphonamides were introduced in 1935 and approximately 10 years later 20% of clinical isolates of Neisseria gonorrhoeae had become resistant. Similar increases in sulphonamide resistance were found in streptococci, coliforms and other bacteria. Penicillin was first used in 1941, when less than 1 % of Staphylococcus aureus strains were resistant to its action. By 1947,3 8% of hospital strains had acquired resistance and currently over 90% of Staph, aureus isolates are resistant to penicillin. Increasing resistance to antibiotics is a consequence of selective pressure, but the actual incidence of resistance varies between different bacterial species. For example, ampicillin resistance inEscherichia coli, presumably under similar selective pressure as Staph, aureus with penicillin, has remained at a level of 30-40% for mai years with a slow rate of increase. Streptococcus pyogenes, another major pathogen, has remained susceptible to penicillin since its introduction, with no reports of resistance in the scientific literature. Equally, it is well recognized that certain bacteria are unaffected by specific antibiotics. In other words, these bacteria have always been antibiotic-resistant. 

Plasmids have the ability to transfer within and between species and can therefore be acquired from other bacteria as well as a consequence of cell division. This property makes plasmid-acquired resistance much more threatening in terms ofthe spread of antibiotic resistance than resistance acquired due to chromosomal mutation. Plasmids also harbour transposons (section 2.1.3), which enhances their ability to transfer antibiotic resistance genes. 

Acquired resistance due to decreased permeability by mutations affecting membrane transport have also been reported in other bacteria. 

Phenoxyethanol (2-phenoxyethanol). Typical in-use concentration 1%. It is more active against Ps. aeruginosa than against other bacteria and is usually combined with other preservatives such as the hydroxybenzoates to broaden the spectrum of antimicrobial activity. 

Lactamases Bacillus cereus (or other bacteria, as appropriate) Sterility testing, treatment of penicillin-induced allergic reaction 2.4.4, 4.5... 

These reductases play a key role both in methanogenesis and in the degradation of phenols that carry several nitro groups, which is discussed further in Chapter 9, Part 5. Although these reductases are typically found in methanogens, they have been encountered in a number of other bacteria and archaea ... 

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