Maltose transporter

About one equivalent of protons was taken up with each equivalent of methyl a-D-glucopyranoside239 or maltose247 a-TEG was also absorbed with protons. In addition, Serrano245 and Palacios and Serrano248 found maltose transport to be coupled to the electrochemical, proton gradient, but that entry was independent of the intracellular concentration of ATP. 

J. Chen, S. Sharma, F A. Quiocho, and A.L. Davidson. 2001. Trapping the transition state of an ATP-binding cassette transporter Evidence for a concerted mechanism of maltose transport Proc. Natl. Acad. Sci. USA 98 1525-1530. (PubMed) (Full Text in PMC)... 

At the start of the infectious process, lambda phage contacts a nutrient transport protein (the maltose transporter) on the membrane of the . colL Without this membrane-bound protein, the phage cannot infect the . cell. At the start of the infectious process, filamentous phage contacts the pilus of the . coli. Without this extracellular structure, the phage cannot infect the E. coli. When lambda phage reproduces, it causes the bacterial cdl to burst, and the . coli is killed. When filamentous phage reproduces, it leaves the . edi in a harmless budding process, and the E. coli survives. 

Davidson, A.L., Laghaeian, S.S., and Manriering, D.E. (1996) The maltose transport system of Escherichia coli displays positive cooperativity in ATP hydrolysis. The Journal of Biological Chemistry, 271 (9), 4858-4863. 

Khare, D., Oldham, M.L., Orelle, C., Davidson, A.L., and Chen, J. (2009) Alternating access in maltose transporter mediated by rigid-body rotations. Mol Cell, 33, 528-536. 

Chen, J., Sharma, S., Quiocho, F, A., and Davidson, A, L. 2001. Trapping the transition stale of an A I P-bmding cassette trans porter Evidence for a concerted mechanism of maltose transport. Proc. Natl Acad. Sci. U. S. A. 98 1525-1530. 

FIGURE 11-13 Membrane proteins with -barrel structure. Five examples are shown, viewed in the plane of the membrane The first four are from the E. coli outer membrane. FepA (PDB ID 1 FEP), involved in iron uptake, has 22 membrane-spanning /3 strands. OmpLA (derived from PDB ID 1 QD5), a phospholipase, is a 12-stranded /3 barrel that exists as a dimer in the membrane. Maltoporin (derived from PDB ID 1 MAL), a maltose transporter, is a trimer, each monomer constructed of 1 6 /3 strands. TolC (PDB ID 1 EK9), another transporter, has three separate subunits, each contributing four /3 strands in this 12-stranded barrel. The Staphylococcus aureus a-hemolysin toxin (PDB ID 7AHL top view below) is composed of seven identical subunits, each contributing one hairpin-shaped pair of /3 strands to the 14-stranded barrel. 

Dahl, M.K. and Manson, M.D. (1985). Interspedfic reconstitution of maltose transport and chemotaxis in Escherichia coli with maltose-binding protein from various enteric bacteria. J. Bacteriol. 164,1057—1063. 

Manson, M.D., Boos, W., Bassford, P.J. and Rasmussen, B.A. (1985). Dependence of maltose transport and chemotaxis on the amount of maltose-binding protein. J. Biol. Chem. 260, 9727-9733. 

The best-studied systems to date are those for the uptake of maltose, histidine, siderophores and vitamin B12. Typical of all the ABC-type importers are the soluble binding proteins, which bind the substrate with high affinity. Early studies revealed that many binding proteins could be extracted from Gramnegative bacteria by an osmotic shock procedure, giving rise to the term osmotic-shock-sensitive transport systems. It still holds true that the majority... 

Mourez, M., Jehanno, M., Schneider, E. and Dassa, E. (1998). In vitro interaction between components of the inner membrane complex of the maltose ABC transporter of Escherichia colt modulation by ATP, Mol. Microbiol., 30, 353-363. 

Diederichs, K, Diez, J., Greller, G., Muller, C., Breed, J., Schnell, C., Vonrhein, C., Boos, W. and Welte, W. (2000). Crystal structure of MalK, the ATPase subunit of the trehalose/maltose ABC transporter of the archaeon Thermococcus litoralis, EMBO J., 19, 5951-5961. 

The thermodynamics of the maltose-binding protein of E. coli (MalE) have been studied using both DSC and ITC.117 This protein is a periplasmic component of the transport system for malto-oligosaccharides and is used widely as a carrier... 

The third group is that of compounds which may potentially be transported by the PTS and inhibit cAMP production. Cellulase synthesis is initiated after these compounds are consumed for cell growth. This group includes D-glucose, D-fructose, maltose, mannitol, glycerol, sorbitol, and -methyl glucoside. The presence of these compounds in Solka Floe fermentations, enhanced enzyme yields (132 to 254%) but the time required to complete cellulase synthesis took longer (106 to 148%) than the control. 

Complexes of alkali metals and alkaline-earth metals with carbohydrates have been reviewed in this Series,134 and the interaction of alkaline-earth metals with maltose has been described.135 Standard procedures for the preparation of adducts of D-glucose and maltose with the hydroxides of barium, calcium, and strontium have been established. The medium most suitable for the preparation of the adduct was found to be 80% methanol. It is of interest that the composition of the adducts, from D-glucose, maltose, sucrose, and a,a-trehalose was the same, namely, 1 1, in all cases. The value of such complex-forming reactions in the recovery of metals from industrial wastes has been recognized. Metal hydroxide-sugar complexes may also play an important biological role in the transport of metal hydroxides across cell membranes. 

Complex medium for inducing protoplasts 15 238 Saccharomyces carlsbergensis protoplasts active transport induced with 100 mM maltose + 17 mM D-glucose... 

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