Factors microbial toxicity

The availability of pesticides in soil is a critical factor in the induction or inhibition of enhanced biodegradation. The pesticides, whether toxic to the microbes or serving as a suitable substrate, should be available to the microorganisms to exert their toxicity or provide nutrient value. Thus, availability, low microbial toxicity, and high nutritive value seem to be the properties that could favor enhanced degradation of a pesticide. 

The bulk of the allelopathy literature has dealt with direct toxic effects on other plants. However, as developed in this review, it is obvious that allelochemicals may have a major impact on plant root-microbial interactions. Such interactions could lead to growth inhibition in the microorganisms (or in roots) and affect other factors of the root-microbe association resulting in effects... 

Without appropriate cleanup measures, BTEX often persist in subsurface environments, endangering groundwater resources and public health. Bioremediation, in conjunction with free product recovery, is one of the most cost-effective approaches to clean up BTEX-contaminated sites [326]. However, while all BTEX compounds are biodegradable, there are several factors that can limit the success of BTEX bioremediation, such as pollutant concentration, active biomass concentration, temperature, pH, presence of other substrates or toxicants, availability of nutrients and electron acceptors, mass transfer limitations, and microbial adaptation. These factors have been recognized in various attempts to optimize clean-up operations. Yet, limited attention has been given to the exploitation of favorable substrate interactions to enhance in situ BTEX biodegradation. 

Of central importance to the role occupied by host defense peptides within the immune system is the ability of these molecules to distinguish host cells from microbes. It is widely accepted that specific structures and/or functions within the host and microbial cells contribute to this selectivity although host defense peptide localization and regulated expression may also be contributing factors for reducing the toxicity associated with host defense peptides. The following sections discuss the recent literature highlighting this selectivity. 

Primor, N., Parness, J., and Zlotkin, E. (1978). Paradaxin the toxic factor from the skin secretion of the flatfish Paradachirus marmoratus (Soleidae). In Toxins Animals, Plants and Microbial, ed. P. Rosenberg. Oxford Pergamon Press. 

The main factors influencing CP remediation include temperature, the properties of the environmental matrix, the toxicity of CPs or other compounds, and the composition of indigenous or added microbial cultures (Crawford Mohn, 1985). Unlike many other xenobiotics, CPs undergo insignificant volatilization (Valo Salkinoja-Salonen, 1986 Lamar et al., 1990b Mueller et al., 1991a). The temperature, the contaminant bioavailability, the possible process amendments and the effects of additional contaminants are discussed below. 

Baath, E. (1989). Effects of heavy metals in soil on microbial processes and populations (a review). Water, Air, and Soil Pollution, 47, 335—79-Babich, H. Stotzky, G. (1980). Environmental factors that influence the toxicity of heavy metal and gaseous pollutants to microorganisms. Critical Reviews in Microbiology, 8,99-145. Babich, H. Stotzky, G. (1985). Heavy metal toxicity to microbe-mediated ecologic... 

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