ISSN:
1432-1424
Keywords:
Pseudomonas aeruginosa
;
cation cotransport
;
branched-cham amino acids
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
Notes:
Summary A transport system for branched-chain amino acids (designated as LIV-II system) inPseudomonas aeruginosa requires Na+ for its operation. Coupling cation for this system was identified by measuring cation movement during substrate entry using cation-selective electrodes. Uptakes of Na+ and Li− were induced by the imposition of an inwardly-directed concentration gradient of leucine, isoleucine, or valine. No uptake of H− was found, however, under the same conditions. In addition, effects of Na+ and Li+ on the kinetic property of the system were examined. At chloride salt concentration of 2.5mm, values of apparentK m andV max for leucine uptake were larger in the presence of Na+ than Li+. These results indicate that the LIV-II transport system is a Na+(Li+)/substrate cotransport system, although effects of Na+ and Li+ on kinetics of the system are different.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01871083
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