Membrane-bound Acid Phosphatase Research Articles

Further studies on the lethal effect of long-chain fatty acids on mycobacteria.

Mycobactericidal activity of long-chain fatty acids was confirmed by in vitro exposure of BCG. The killing effect was accompanied by inhibition of the membrane-bound acid phosphatase activity. Such active fatty acids were those having a stronger hemolytic activity (e.g., C12:0, C14:0, C18:1, C18:2). Heat-killed BCG cells or their cell walls adsorbed the toxic fatty acids, whereas the fatty acid-insensitive E. coli cells did not. It was suggested that the mycobactericidal action of long-chain fatty acids is due to their detergent-like action on the cytoplasmic membrane, and that the determinant factor for the fatty acid-sensitivitiy of bacteria is the property of the cell wall by which fatty acids are adsorbed so that the active site is brought into contact with the inner membrane.

Aging Stresses on Physiological and Biochemical Activities of Crimson Clover ( Trifolium incarnatum L. var. Dixie) Seeds 1

To explore the mechanism of aging, seed lots of crimson clover (Trifolium incarnatum L.) which had been subjected to different aging stresses were analyzed for germinability, growth rate, membrane permeability, content of soluble metabolites, ribonucleic acids (RNA), deoxyribonucleic acid (DNA), soluble protein, acid phosphatase and cytochrome c oxidase activities, and ability to incorporate phenylalanine and uridine into protein and RNA. Aging in quiescent seeds appears to be related to a gradual inactivation of pre-existing enzymes and systems for protein and RNA synthesis, and a hydrolysis of structural components. Membrane-bound acid phosphatase was more resistant to aging stresses than the soluble acid phosphatase. High seed water content and high storage temperature did not reduce the quantity of preexisting RNA or DNA in seeds; qualitative changes in conserved RNA and DNA were not precluded, however.