Multiple limited growth

If oxygen limits growth and multiplication of aerobic bacteria, the adaptive value and inductive mechanism of poly(3HB) synthesis are quite similar to those outlined for nitrogen limitation. 2/H/ generated are not oxidized via elec-... 

Wilhelm, S. W. and Trick, C. G. (1994). Iron-limited growth of cyanobacteria -multiple siderophore production is a common response, Limnol. Oceanogr., 39, 1979-1984. 

Law, A. T. and Button, D. K. (1977). Multiple-carbon-source-limited growth kinetics of a marine coryneform bacterium, J. Bacteriol., 129, 115-123. 

Because of the failure of the Monod equation to find universal applicability, many researchers have suggested variations on the form of this equation in attempts to better characterize the kinetic behavior of substrate-limited growth of microorganisms. There are several more complex mathematical models that take into account not only inhibition by substrates and/or products of biochemical reactions, but also other factors, such as cell death and cell maintenance effects and multiple limiting substrates (5,6). 

The metabolic response of P. putida KT2442 producing high levels of poly-hydroxyalkanoate under single- and multiple-nutrient-limited growth highlights from a multi-level omics approach. Micrafe. Cell Fact, 11, 34. 

In the case of mcZ-PHAs, a Swiss group reports the continuous, growth-associated production of poly(3-hydroxyalkanoate-co-3-hydroxyalkenoates) in one-stage chemostat cultures of Pseudomonas putida ATCC 29147 in a single CSTR. The applied substrates encompassed 5-phenylvalerate, octanoate and 10-undecenoate. Multiple nutrient limited growth conditions were chosen at a dilution rate of D = 0.1 h . Different mixtures of the substrates in the feed resulted in the formation of copolyesters with varying compositions and different amounts of aromatic and unsaturated side chains that make the products accessible for further modification. Based on the results, the authors conclude that the steady state conditions in a continuous culture provide a strategy especially suited for the production of tailored PHA copolymers [117]. 

Zinn M, Witholt B, Egh T (2001) Occurrence, synthesis and medical application of bacterial polyhydroxyalkanoate. Adv Drug DeUv Rev 53 5-21 Zinn M, Hartmann R, Pletscher E, Geiger T, Witholt B, EgU T (2002) Tailored biosynthesis of polyhydroxyalkanoate under multiple-nutrient-Umited growth conditions Zinn M, Witholt B, Egli T (2004) Dual nutrient limited growth models, experimental observations, and applications. J Biotechnol 113 263-279... 

Chloramphenicol (Chloromycetin) interferes witii or inhibits protein synthesis, a process necessary for the growth and multiplication of microorganisms. This is a potentially dangerous drug (see below), and therefore its use is limited to serious infections when less potentially dangerous drugp are ineffective or contraindicated. 

Aluminium toxicity is a major stress factor in many acidic soils. At soil pH levels below 5.0, intense solubilization of mononuclear A1 species strongly limits root growth by multiple cytotoxic effects mainly on root meristems (240,241). There is increasing evidence that A1 complexation with carboxylates released in apical root zones in response to elevated external Al concentration is a widespread mechanism for Al exclusion in many plant species (Fig. 10). Formation of stable Al complexes occurs with citrate, oxalate, tartarate, and—to a lesser extent— also with malate (86,242,243). The Al carboxylate complexes are less toxic than free ionic Al species (244) and are not taken up by plant roots (240). This explains the well-documented alleviatory effects on root growth in many plant species by carboxylate applications (citric, oxalic, and tartaric acids) to the culture media in presence of toxic Al concentrations (8,244,245) Citrate, malate and oxalate are the carboxylate anions reported so far to be released from Al-stressed plant roots (Fig. 10), and Al resistance of species and cultivars seems to be related to the amount of exuded carboxylates (246,247) but also to the ability to maintain the release of carboxylates over extended periods (248). In contrast to P deficiency-induced carboxylate exudation, which usually increases after several days or weeks of the stress treatment (72,113), exudation of carboxylates in response to Al toxicity is a fast reaction occurring within minutes to several hours... 

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