scispace - formally typeset
Search or ask a question

Showing papers by "Trond Lamark published in 1992"


Journal ArticleDOI
TL;DR: There is evidence that glycine betaine (betaine) which was synthesized from choline was excreted and reaccumulated in osmoregulating cells of Escherichia coli.
Abstract: We present evidence that glycine betaine (betaine) which was synthesized from choline was excreted and reaccumulated in osmoregulating cells of Escherichia coli. Choline which was accumulated in bet mutants defective in betaine synthesis was shown to be excreted in response to betaine uptake. Our data suggest that E. coli has efflux systems for betaine and choline which are independent of the uptake systems for these metabolites. The ProU system of E. coli, but not that of Salmonella typhimurium, can mediate low-affinity choline uptake.

73 citations