title: Neutral amino acid transport in Pseudomonas fluorescens.
abstract: Membrane transport of beta-alanine, l-alanine, and l-proline was studied in a beta-alanine transaminaseless mutant (strain 67) of Pseudomonas fluorescens. In this mutant beta-alanine is metabolically inert, and it was therefore possible to demonstrate active transport of this substrate in the absence of intracellular catabolism. The permease which catalyzes the uptake of beta-alanine also transports l-proline and l-alanine. This common transport system was distinguished from permeases which transport only l-alanine and only l-proline by competition studies in strain 67 and by studies of transport specificity in a permeaseless mutant (strain 67/4MTR).
mesh_terms: D000409:Alanine / Q000378:metabolism*; D000410:Alanine Transaminase / Q000378:metabolism; D000596:Amino Acids / Q000494:pharmacology; D001693:Biological Transport, Active; D002247:Carbon Isotopes; D002462:Cell Membrane / Q000378:metabolism; D002854:Chromatography, Paper; D003486:Cyanides / Q000494:pharmacology; D003864:Depression, Chemical; D004140:Dinitrophenols / Q000494:pharmacology; D005827:Genetics, Microbial; D026901:Membrane Transport Proteins / Q000378:metabolism; D009154:Mutation; D011392:Proline / Q000378:metabolism*; D011549:Pseudomonas / Q000201:enzymology / Q000378:metabolism*; D013237:Stereoisomerism
chemical_list: D000596:Amino Acids; D002247:Carbon Isotopes; D003486:Cyanides; D004140:Dinitrophenols; D026901:Membrane Transport Proteins; D011392:Proline; D000410:Alanine Transaminase; D000409:Alanine