Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Disaccharides as a new class of nonaccumulated osmoprotectants for Sinorhizobium meliloti
Autore:
Gouffi, K; Pica, N; Pichereau, V; Blanco, C;
Indirizzi:
Univnes,nes 1, CNRS, UPRES A 6026, Grp Membranes & Osmoregulat, F-35042 Ren Univ Rennes 1 Rennes France F-35042 Membranes & Osmoregulat, F-35042 Ren
Titolo Testata:
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
fascicolo: 4, volume: 65, anno: 1999,
pagine: 1491 - 1500
SICI:
0099-2240(199904)65:4<1491:DAANCO>2.0.ZU;2-M
Fonte:
ISI
Lingua:
ENG
Soggetto:
STRESSED RHIZOBIUM-MELILOTI; ESCHERICHIA-COLI; GLYCINE BETAINE; BREVIBACTERIUM-LINENS; ERWINIA-CHRYSANTHEMI; SOLUTE ACCUMULATION; OSMOTIC ADJUSTMENT; MOLECULAR-BIOLOGY; GENE-EXPRESSION; ORGANIC SOLUTES;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Agriculture,Biology & Environmental Sciences
Life Sciences
Citazioni:
62
Recensione:
Indirizzi per estratti:
Indirizzo: Blanco, C Univlieu,Av 1, CNRS, UPRES A 6026, Grp Membranes & Osmoregulat, Campus Beau Univ Rennes 1 Campus Beaulieu,Av Gen Leclerc Rennes France F-35042
Citazione:
K. Gouffi et al., "Disaccharides as a new class of nonaccumulated osmoprotectants for Sinorhizobium meliloti", APPL ENVIR, 65(4), 1999, pp. 1491-1500

Abstract

Sucrose and ectoine (1,4,5,6-tetrahydro-2-methyl-4-pyrimidine carboxylic acid) are very unusual osmoprotectants for Sinorhizobium meliloti because these compounds, unlike other bacterial osmoprotectants, do not accumulate ascytosolic osmolytes in salt-stressed S. meliloti cells. Here, we show that, in fact, sucrose and ectoine belong to a new family of nonaccumulated sinorhizobial osmoprotectants which also comprises the following six disaccharides: trehalose, maltose, cellobiose, gentiobiose, turanose, and palatinose. Also, several of these disaccharides were very effective exogenous osmoprotectants for strains of Rhizobium leguminosarum biovars phaseoli and trifolii. Sucrose and trehalose are synthesized as endogenous osmolytes in various bacteria, but the other five disaccharides had never been implicated before in osmoregulation in any organism. All of the disaccharides that acted as powerful osmoprotectants in S. meliloti and R. leguminosarum also acted as very effective competitors of [C-14]sucrose uptake in salt-stressed cultures of these bacteria. Conversely, disaccharides that were not osmoprotective for S. meliloti and R. leguminosarum did not inhibit sucrose uptake in these bacteria. Hence, disaccharide osmoprotectants apparently shared the same uptake routes in these bacteria. Natural-abundance C-13 nuclear magnetic resonance spectroscopy and quantification of cytosolic solutes demonstrated that the novel disaccharide osmoprotectants were not accumulated to osmotically significant levels in salt-stressed S. meliloti cells; rather, these compounds, like sucrose and ectoine, were catabolized during early exponential growth, and contributed indirectly to enhance the cytosolic levels oftwo endogenously synthesized osmolytes, glutamate and the dipeptide N-acetylglutaminylglutamine amide. The ecological implication of the use of thesedisaccharides as osmoprotectants is discussed.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 06/07/20 alle ore 04:53:58