Culture bacterial

Very small amounts of 2-hydroxy-4-methylthiazole-5-acetic acid were determined by chromatographic techniques in bacterial culture medium (41). 

Amino acids protein hydrolysates, bacterial cultures, food, urine various... 

Bakterien wachstum, n. bacterial growth, zahlung, /. bacterial count, -zucbtung, /. bacterial culture. 

Into each of 27 Erlenmeyer flasks are placed 150 mg of Kendall s Compound F (hydrocortisone). The flasks and contents are then sterilized for 15 minutes at 15 pounds steam pressure (120 C). To each flask are then added 5.0 ml of ethanol. The 24-hour bacterial culture is then transferred asepticaliy and the resulting suspensions are Shaken on a shake table at 220 rpm and 28°C for 48 hours. The pH at the end of the shake period is 7.0. 

Preparation of semisynthetic aequorins. The best yield of semisynthetic aequorins can be obtained by using the apoaequorin prepared from aequorin immediately before use. Apoaequorin stored, even for 2-3 days, or recombinant apoaequorin isolated from a bacterial culture will give a significantly lower yield due to their somewhat unfolded molecular conformation. Fresh apoaequorin prepared by the Ca2+-triggered luminescence reaction appears to have the conformation best suited for regeneration. 

The bacterial culture converts a portion of the supplied nutrient into vegetative cells, spores, crystalline protein toxin, soluble toxins, exoenzymes, and metabolic excretion products by the time of complete sporulation of the population. Although synchronous growth is not necessary, nearly simultaneous sporulation of the entire population is desired in order to obtain a uniform product. Depending on the manner of recovery of active material for the product, it will contain the insolubles including bacterial spores, crystals, cellular debris, and residual medium ingredients plus any soluble materials which may be carried with the fluid constituents. Diluents, vehicles, stickers, and chemical protectants, as the individual formulation procedure may dictate, are then added to the harvested fermentation products. The materials are used experimentally and commercially as dusts, wettable powders, and sprayable liquid formulations. Thus, a... 

By separation Irom bacterial culture such as Escherichia coli, Serratia marcescens, Erwinia aroideae, Erwinia atroseptica, Erwinia carotovora. 

This apparent low efficiency for reducing N2 was observed under conditions of saturating N2 and is not due to restrictions in electron transfer rate. Furthermore, the low efficiency is mirrored in bacterial cultures at 30°C (185). 

Tsuchii, A. and Takeda, K., Rubber-degrading enzyme from a bacterial culture, Appl. Bnviron. Microbiol, 56, 269, 1990. 

Several studies were performed on the optimization of expression levels of ELP proteins in E. coli. In a recent example, the expression protocol was optimized for an ELP fusion with green fluorescent protein (GFP). This fusion protein was expressed and purified in a yield of 1.6 g/L of bacterial culture, which finally yielded 400 mg GFP/L bacterial culture. This extremely high yield was found after uninduced expression in nutrient-rich medium supplemented with phosphate, glycerol and certain amino acids, such as proline and alanine [234]. The influence of fusion order was also examined and it was found that positioning the ELP at the C-terminus of target protein resulted in significantly higher expression levels [35]. 

The previous ELP fusions all are examples of protein purification in which the ELP is covalently connected to the protein of choice. This approach is suitable for the purification of recombinant proteins that are expressed to high levels, but at very low concentrations of ELP the recovery becomes limited. Therefore this approach is not applicable for proteins expressed at micrograms per liter of bacterial culture, such as toxic proteins and complex multidomain proteins. An adjusted variant of ITC was designed to solve this problem. This variant makes use of coaggregation of free ELPs with ELP fusion proteins. In this coaggregation process, an excess of free ELP is added to a cell lysate to induce the phase transition at low concentrations of... 

Extraction of Sodium Channel Blockers. A review of published reports shows that methods for purification of sodium channel blockers from bacterial cultures are similar to techniques for isolation of TTX and STX from pufferfish and dinoflagellates (30, 31, 38, 39). Typically, cell pellets of bacterial cultures are extracted with hot 0.1% acetic acid, the resulting supernatant ultra-filtered, lyo-philized, and reconstituted in a minimal volume of 0.1% acetic acid. Culture media can also be extracted for TTX by a similar procedure (Ji). Both cell and supernatant extracts are analyzed further by gel filtration chromatography and other biological, chemical, and immunological methods. Few reports describe purification schemes that include extraction of control samples of bacteriological media (e.g., broths and agars) which may be derived from marine plant and animal tissues. 

It is emphasized that some investigations show that bacterial cultures contain TTX-like substances which are not detected by mouse bioassay and are "difficult to detect" by HPLC and GC-MS analyses. Structural analyses of these substances with other techniques was not reported. 

Chromatographic Characterization of TTXs. The vast majority of reports have identified TTX and anhydro-TTX in bacterial cultures using HPLC, TLC, and GC-MS. Yasumoto et al. (30) showed that TTX-like substances extracted from a Pseudomonas sp. culture could bind to activated charcoal at pH 5.5 and be eluted with 20% ethanol in 1% acetic acid. In addition, HPLC analysis demonstrated TTX and anhydro-TTX-like fluorophors following strong base treatment. These compounds migrated on silica gel comparably to TTX and anhydro-TTX. Furthermore, when analyzed by electron ionization (EI)-MS and fast atom... 

The optimum temperature varies widely from species to species but in general the common moulds will grow better at 22-25 °C than most human pathogenic and commensal bacteria. It is customary, therefore, to incubate mould cultures at lower temperatures than bacterial cultures. 

Changes in the population of viable bacteria in an environment are determined by means of a viable count, and aplot of this count against time gives a dynamic picture of any pattern of change (see Fig. 11.1, curve A). The typical growth curve of a bacterial culture is constructed from data obtained in this w. The pattern of bacterial death in a lethal environment m be obtained by the same technique, when a death or mortality curve is obtained (Fig. 11.1, curve C). 

The Kelsey-Sykes (KS) test. Having regard to the many disadvantages alleged against the RW and CM tests, attempts were made and published in the early 1960s to find improved test methods. The foundations for the new test were laid by Kelsey et al. in 1965, and with the collaboration of the late G. Sykes and ofisobel M. Maurer, the Kelsey-Sykes test was evolved. This test embodied several principles. Firstly, it was a capacity test. Here a bacterial inoculum was added to the disinfectant in three successive lots at 0, 1 and 5 minutes. This is the principle of a capacity test where the capacity or lack of capacity ofthe disinfectant to destroy successive additions of a bacterial culture is tested. 

Luciferase assay. In this technique, firefly luciferase is used to measure small amounts of adenosine triphosphate (ATP) in a bacterial culture, ATP levels being reduced by the inhibitory action of aminoglycoside antibiotics. This method may find more application in the future as more active and reliable luciferase preparations become available. 

Tett VA, AJ Willetts, HM Lappin-Scott (1994) Enantioselective degradation of the herbicide mecoprop [2-methyl-4-chlorophenoxypropionic acid] by mixed and pure bacterial cultures. FEMS Microbiol Ecol 14 191-200. 

El-Fantroussi S (2000) Enrichment and molecular characterization of bacterial culture that degrades methoxy-methyl urea herbicides and their aniline derivatives. Appl Environ Microbiol 66 5110-5115. 

Foght JM, DL Gutnick, DWS Westlake (1989) Effect of emulsan on biodegradation of crude oil by pure and mixed bacterial cultures. Appl Environ Microbiol 55 36-42. 

These results may be viewed in the wider context of interactions between potential ligands of multifunctional xenobiotics and metal cations in aquatic environments and the subtle effects of the oxidation level of cations such as Fe. The Fe status of a bacterial culture has an important influence on synthesis of the redox systems of the cell since many of the electron transport proteins contain Fe. This is not generally evaluated systematically, although the degradation of tetrachloromethane by a strain of Pseudomonas sp. under denitrifying conditions clearly illustrated the adverse effect of Fe on the biotransformation of the substrate (Lewis and Crawford 1993 Tatara et al. 1993). This possibility should therefore be taken into account in the application of such organisms to bioremediation programs. 

Van den Wijngaard AJ, DB Janssen, B Withold (1989) Degradation of epichlorohydrin and halohydrins by bacterial cultures isolated from freshwater sediment. J Gen Microbiol 135 2199-2208. 

Hatzinger PB, K McClay, S Vainberg, M Tugusheva, CW Condee, RJ Steffan (2001) Biodegradation of methyl terf-butyl ether by a pure bacterial culture. Appl Environ Microbiol 67 5601-5607. 

Schowanek D, W Verstraete (1990) Phosphonate utilization by bacterial cultures and enrichments from environmental samples. Appl Environ Microbiol 56 895-903. 

Occasionally, biotransformation in the absence of substantial biodegradation may be acceptable. Dicyclopentadiene is produced pyrolytically in petrochemical plants and has a nauseating and penetrating odor. Although it could be degraded by a mixed bacterial culture, the major part was transformed into a series of oxygenated compounds that were presumed to be less malodorous (Stehmeier et al. 1996 Shen et al. 1998). 

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