title: Transport of lysine and hydroxylysine in Streptococcus faecalis.
abstract: Data are presented which support the view that l-lysine is transported by two systems in Streptococcus faecalis. The system with the higher affinity for l-lysine appears to be specific for l-lysine among the common amino acids and to require an energy source. The second system transports both l-lysine and l-arginine and does not appear to require an energy source. Both of these systems will accept hydroxy-l-lysine as a substrate as shown by the energy requirement for hydroxy-l-lysine transport and by the inhibition of uptake by l-arginine as well as by l-lysine. The affinity of both systems appears to be considerably lower for hydroxy-l-lysine than for l-lysine. A mutant of S. faecalis which is resistant to the growth inhibitory action of hydroxy-l-lysine appears to differ from the parent strain by having a defective l-lysine-specific transport system. In this mutant, hydroxy-l-lysine is not readily transported via the l-lysine-specific system because of the mutation or via the second system because of the high concentration of l-arginine present in the growth medium. This overall lack of transport prevents hydroxy-l-lysine from reaching inhibitory levels within the cell.
mesh_terms: D001120:Arginine / Q000494:pharmacology; D001692:Biological Transport; D002247:Carbon Isotopes; D003470:Culture Media; D013293:Enterococcus faecalis / Q000254:growth & development / Q000378:metabolism*; D005374:Filtration; D005827:Genetics, Microbial; D005947:Glucose / Q000494:pharmacology; D006639:Histidine / Q000494:pharmacology; D006901:Hydroxylysine / Q000378:metabolism; D007461:Iodoacetates / Q000494:pharmacology; D008239:Lysine / Q000378:metabolism*; D009154:Mutation; D013237:Stereoisomerism
chemical_list: D002247:Carbon Isotopes; D003470:Culture Media; D007461:Iodoacetates; D006901:Hydroxylysine; D006639:Histidine; D001120:Arginine; D005947:Glucose; D008239:Lysine