+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Dissection of discrete kinetic events in the binding of antibiotics and substrates to the galactose-H+ symport protein, GalP, of Escherichia coli

, : Dissection of discrete kinetic events in the binding of antibiotics and substrates to the galactose-H+ symport protein, GalP, of Escherichia coli. Antonie van Leeuwenhoek 65(4): 349-358

GalP is the membrane protein responsible for H+-driven uptake of D-galactose into Escherichia coli. It is suggested to be the bacterial equivalent of the mammalian glucose transporter, GLUT1, since these proteins share sequence homology, recognize and transport similar substrates and are both inhibited by cytochalasin B and forskolin. The successful over-production of GalP to 35-55% of the total inner membrane protein of E. coli has allowed direct physical measurements on isolated membrane preparations. The binding of the antibiotics cytochalasin B and forskolin could be monitored from changes in the inherent fluorescence of GalP, enabling derivation of a kinetic mechanism describing the interaction between the ligands and GalP. The binding of sugars to GalP produces little or no change in the inherent fluorescence of the transporter. However, the binding of transported sugars to GalP produces a large increase in the fluorescence of 8-anilino-1-naphthalene sulphonate (ANS) excited via tryptophan residues. This has allowed a binding step, in addition to two putative translocation steps, to be measured. From all these studies a basic kinetic mechanism for the transport cycle under non-energized conditions has been derived. The ease of genetical manipulation of the galP gene in E. coli has been exploited to mutate individual amino acid residues that are predicted to play a critical role in transport activity and/or the recognition of substrates and antibiotics. Investigation of these mutant proteins using the fluorescence measurements should elucidate the role of individual residues in the transport cycle as well as refine the current model.


PMID: 7832591

Other references

Kohn, R.; Dongowski, G.; Bock, W., 1985: The distribution of free and esterified carboxyl groups within the pectin molecule after the action of pectin esterase from Aspergillus niger and oranges. By reaction of pectin esterase (PE) from Aspergillus niger and oranges as well as lye, with 95% esterified citrus and apple pectin we prepared series of preparations with degrees of esterification between 35 and 77%. In these partial deesterified...

McIlroy, A.L., 1924: X-Ray Demonstration of Fœtus in Utero. Proceedings of the Royal Society of Medicine 17(Obstet Gynaecol Sect): 50-51

Bachinsky W.B.; Linzer M.; Weld L.; Estes N.A.M.IIi, 1992: Usefulness of clinical characteristics in predicting the outcome of electrophysiologic studies in unexplained syncope. Guidelines for the use of electrophysiologic studies in syncope have not yet been formulated. To confirm the sensitivity and specificity of a previously derived model to predict the results of electrophysiologic testing in syncope, the importance...

Miguérès, J.; Jover, A.; Lareng, M.B.; Cantegril, A.; Puel, J.; Lefèvre, J.C.; Larrouy, H., 1972: The role of respiratory syncytial virus in bronchopulmonary pathology in adults. Revue de Tuberculose et de Pneumologie 36(3): 417-430

Wyllie, A.; Zhang,; Casswell, S., 2000: Risk functions for frequency of alcohol-related negative consequences: New Zealand survey data. Aims. To examine the dose-response relationship between self-reported alcohol consumption and levels of self-reported negative consequences of drinking. Design. Data from 10 general population random sample surveys over the years 1990-1997 were co...

Ennis M.; Rizvi T.A.; Shipley M.T.; Behbehani M.M.; Smith D.; Van Bockstaele E.J.; Luppi P.; Aston Jones G., 1991: Projections from the periaqueductal gray pag to the periambigual area relation to vagal output neurons. Society for Neuroscience Abstracts 17(1-2): 611

Dietrich, J.E., 2013: Adolescence is risky business. Journal of Pediatric and Adolescent Gynecology 26(1): 2-2

Lacerda, F.Mirian.Moura.; Carvalho, W.Roberto.Gomes.; Hortegal, E.Viana.; Cabral, N.Anielly.Lima.; Veloso, H.Jane.Ferreira., 2016: Factors associated with dietary supplement use by people who exercise at gyms. OBJECTIVE To assess the factors associated with the use of dietary supplements by people who exercise at gyms.METHODS A cross-sectional study with a sample defined by convenience, considering the number of gyms registered in the Conselho Regional...

Yanchenko, A.A.; Gudz' , Y.V., 1991: Features of breeding early hybrid maize as a catch crop in the irrigated zone of the Ukraine. As a result of evaluation and selection of breeding material following afterharvest sowing, inbred lines, varieties and synthetic populations best adapted to the local conditions were obtained, notably the early and midearly lines 4077/84, 4015/26...

Watkins, B.; Montgomery, A.B., 1989: Conceptions of athletic excellence among children and adolescents. Youth in grades 3, 6, 9, and 12 were interviewed about their beliefs regarding athletic excellence. A set of open-ended questions assessed beliefs about the source of athletic ability and the differences between excellent athletes and others. Resp...