[Biochemical adaptation of the barley root cells to toxic substances. 1. Effect of aluminum on the phosphohydrolase activity].
Acid phosphatase (AP) and two nucleotidases with a top affinity to ATP and Ca (AN1) or AMP and Mg (AN2) were found among acid phosphohydrolases of the apoplast. After 15 min aluminum chloride at 100 microM induced activity of both membrane-bound and soluble phosphohydrolases. The highest induction of the enzymes by aluminum was observed at pH 4.5. A relatively high concentration of aluminum chloride (2 mM) stimulated AN2 and inhibited AN1, while AP activity remained unaltered. We propose that they activation of membrane-bound and soluble acid phosphohydrolases is one of the protective mechanisms of barley root apoplast against the toxic effect of aluminum chloride.
Tikhaia
N I
NI
Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, Moscow, Russia.
Fedorovskaia
M D
MD
D000222:Adaptation, Physiological; D000077410:Aluminum Chloride; D017607:Aluminum Compounds / Q000633:toxicity*; D002462:Cell Membrane / Q000201:enzymology; D002712:Chlorides / Q000633:toxicity*; D001467:Hordeum / Q000187:drug effects* / Q000201:enzymology / Q000502:physiology; D008861:Microsomes / Q000201:enzymology; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D018517:Plant Roots / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology
D017607:Aluminum Compounds; D002712:Chlorides; D000077410:Aluminum Chloride; D010744:Phosphoric Monoester Hydrolases