Amino acid stress accumulation

Stewart, G.R. Larher, F. (1981). The accumulation of amino acids and related compounds in relation to environmental stress. In Biochemistry of Plants, Vol. V, ed. B.J. Miflin, pp. 609-35. London Academie Press. 

Proline, however, is the predominant amino acid and most interestingly, its betalamic acid adduct indicaxanthin is the major betalain pigment in cactus pear. Proline functions as an osmolyte, accumulating in water- and heat-stressed plant tissues, and in comparison to other amino acids, it exhibits an extraordinarily high solubility of 1623 mg/L water at 25°C. ... 

Despite increased citrate accumulation in roots of Zn-deficient rice plants, root exudation of citrate was not enhanced. However, in distinct adapted rice cultivars, enhanced release of citrate could be observed in the presence of high bicarbonate concentrations in the rooting medium, a stress factor, which is frequently associated with Fe and Zn deficiency in calcareous soils (235) (Hajibo-huid, unpublished). This bicarbonate-induced citrate exudation has been related to improved Zn acquisition in bicarbonate-tolerant and Zn-efficient rice genotypes (Fig. 9) (23S). Increased exudation of sugars, amino acids, and phenolic compounds in response to Zn deficiency has been reported for various dicotyledonous and monocotyledonous plant species and seems to be related to increased... 

Sies H (1991) Oxidative stress oxidants and antioxidants. Academic Press, San Diego Shick JM (2004) The continuity and intensity of ultraviolet irradiation affect the kinetics of biosynthesis, accumulation, and conversion of mycosporine-like amino acids (MAAs) in the coral Stylophora pistillata. Limnol Oceanogr49 223-262 Shick JM, Dunlap WC (2002) Mycosporine-like amino acids and related gadusols biosynthesis, accumulation, and UV-protective functions in aquatic organisms. Annu Rev Physiol 64 223-262... 

The uptake and accumulation of various amino acids in Lactobacillus arabinosus have been described. An extensive investigation of this process using cells deficient in vitamin B6, biotin, and pantothenic acid has shown that all these deficiencies markedly alter the transport process. Accumulation capacity is most severely decreased by a vitamin B6 deficiency. The evidence now available indicates that this does not reflect the direct participation of the vitamin in the transport process, but rather is an indirect effect arising from the synthesis of an abnormal cell wall which renders the cell unusually sensitive to osmotic stress. Amino acid transport in vitamin B6-deficient cells is restored to normal levels by raising the extracellular osmotic pressure or by enabling the cells to synthesize additional wall substance. 

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