Bacteria inhibition

Table 4. Genus Names of Molds, Yeasts, and Bacteria Inhibited by Sorbates ...

To be an effective antibacterial agent, a drng mnst inhibit an enzyme that is present in the bacteria bnt not in the host. One well-known example is a transpeptidase involved in cell wall synthesis in some bacteria. Inhibition prevents bacteria from synthesising their cell wall so that proliferation stops. A drng that inhibits this enzyme is the antibiotic, penicillin first nsed in 1941 (see Chapter 17). However, the first dnrg to inhibit bacterial growth was developed from a dye (Box 3.8). 

Quinolones (bacteriostatic inhibit DNA gyrase) e.g., ciprofloxacin, cinoxacin, enoxacin, norfloxacin Rifampin (bactericidal blocks mRNA synthesis in bacteria, inhibits RNA polymerase)... 

The mechanism(s) by which lactic acid bacteria inhibit or inactivate other bacteria is not totally clear. Daly et al. (1972), Speck (1972), and Gilliland and Speck (1972) have cited evidence which suggests that the following may be involved (1) production of antibiotics such as nisin, diplococcin, acidophilin, lactocidin, lactolin, and perhaps others (2) production of hydrogen peroxide by some lactic acid bacteria (3) depletion of nutrients by lactic acid bacteria, which makes growth of pathogens difficult or impossible (4) production of volatile acids (5) production of acid and reduction in pH (6) production of D-leucine and (7) lowering the oxidation-reduction potential of the substrate. 

Cationic surfactants have applications such as inhibiting the growth of bacteria, inhibiting corrosion, separating phosphate ore from silica and potassium chloride from sodium chloride (flotation agents), and they serve well as fabric softeners, antistatic agents, and hair conditioners. 

Alderton, G., W. H. Ward, and H. L. Fevold Identification of the bacteria-inhibiting, iron-binding protein of egg white as conalbumin. Arch. Biochem. 11, 9 (1946). 

Further, when this same type of inoculum is added after being filtered through fiberglass pads and dense Whatman filter paper and with all methane bacteria inhibited, the Ec value again drops to —480 mv. 

Capsular and extracellular polysaccharides are involved in several aspects of cellular behavior that are tied to bacterial survival and virulence [321]. The capsule layer provides a physical barrier that prevents the bacteria from drying out, aiding in survival outside a host. CPS are also involved in colonization and biofilm formation. In some bacteria CPS promote adherence to surfaces, aiding colonization and biofilm formation, while CPS in other bacteria inhibit adhesion and biofilm formation [344]. 

Tetracycline targets protein synthesis in Plasmodium via a similar mechanism to that seen in bacteria inhibition of chain elongation and peptide bond formation. Eflornithine interferes with the metabolism of the amino acid ornithine in T. brucei gambiense by acting as a suicide substrate for the enzyme ornithine decarboxylase. 

Fig. 6. Antibiotic activity of Sargassum weeds (S. natans, S. fluitans) on their incrusting plants, animals or epiphytic bacteria inhibition was maximal near the Sargasso Sea gyre, the area of optimal growth (from Sieburth, 1962).

Berland, B.R., Bonin, D.J. and Maestrini, S.Y., 1973. Study of bacteria inhibiting marine algae a method of screening which use gliding algae. Mar. Biol. Mar. Oceanogr., 3 1-10. 

One of the most profound developments in the history of modem medicine has been the discovery of antibiotics to control infections. The realization that microbial products could cure infectious diseases spanned approximately sixty-five years of discoveries (8). One of the first modem scientific demonstrations was the observation by Louis Pasteur in 1877 that common bacteria inhibited the growth of a pure anthrax culture. Other observations followed. Then in 1928 it was noted by Alexander Fleming that a culture of a green inhibited the growth of bacteria on an agar plate... 

Desulfovibrio spp. High sulfate levels inhibit methylation while methylation is increased when sulfate levels are low and concentrations of organic fermentation products are high. Sulfide generated by sulfate-reducing bacteria inhibits mercury methylation by rendering mercury less available for methylation. 

Fuglsang, A., Rattray, F. R, Nilsson, D., Nyborg, N. C. B. (2003). Lactic acid bacteria inhibition of angiotensin converting enzyme in vitro and in vivo. Antonie Van Leeuwenhoek, 83, 27-34. 

G. Alderton, W. H. Ward and H. L. Fevold, Identification of the Bacteria-inhibiting, Iron-binding Protein of Egg-white as Conalhumin, Archs Biochem. 77, 9-13 (1946). 

Lindfors K, Blomqvist T, Juuti-Uusitalo K, et al. Live probiotic Bifidobacterium lactis bacteria inhibit the toxic effects induced by wheat gliadin in epithelial cell culture. Clin Exp Immunol. 2008 152 552-558. 

Eftimiadi C, Tonetti M, Cavallero A, Sacco O, Rossi GA. Short-chain fatty adds produced by anaerobic bacteria inhibit phagocytosis by human lung phagocytes. / Infect Dis. 1990 161 138-142. 

FIGURE 11.10 (a) Schematic representation of a penicillin acylase-loaded nanoreactor, (b) Kcture of the MHB agar plate inoculated with bacteria. Inhibition zones 1 control (not permeable polymer-somes) 2 substrate solution 3 nanoreactors prepared at RT 4 nanoreactors prepared at 8°C after incubation for 24 h at 37°C. (c) Schematic representation of enzymatically active, immobilized nanoreactors synthesizing antibiotics. SEM images of E. coli attached to (d) silanized silicon surface, (e) surface with immobilized nonpermeable polymetsomes encapsulating enzyme, (f) surface with immobiUzed nanoreactors. Scale bar 10 mm. (Atk tedfrom Ref. [ 13,53] with permission cf Royal Society of Chemistry.)... 

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