2.02012-10-10 12:15:09 -06002015-06-03 17:25:52 -0600ECMDB23078M2MDB003468beta-L-Rhamnosebeta-L-Rhamnose is an anomer of alpha-L-rhamnose. It is a substrate of the E. coli enzyme L-rhamnose mutarotase. An anomer is a special type of epimer. It is one of two stereoisomers of a cyclic saccharide that differs only in its configuration at the hemiacetal or hemiketal carbon, also called the anomeric carbon.b-6-Deoxy-L-mannoseb-L-Mannomethyloseb-L-RhamnoseBeta-6-Deoxy-L-mannoseBeta-L-MannomethyloseL-Rhamnoseβ-6-Deoxy-L-mannoseβ-L-Mannomethyloseβ-L-RhamnoseC6H12O5164.1565164.068473494(2S,3R,4R,5R,6S)-6-methyloxane-2,3,4,5-tetrolβ-L-rhamnoseC[C@@H]1O[C@H](O)[C@H](O)[C@H](O)[C@H]1OInChI=1S/C6H12O5/c1-2-3(7)4(8)5(9)6(10)11-2/h2-10H,1H3/t2-,3-,4+,5+,6-/m0/s1SHZGCJCMOBCMKK-YJRYQGEOSA-Nlogp-2.39logs0.70solubility8.27e+02 g/llogp-1.9pka_strongest_acidic11.3pka_strongest_basic-3.6iupac(2S,3R,4R,5R,6S)-6-methyloxane-2,3,4,5-tetrolaverage_mass164.1565mono_mass164.068473494smilesC[C@@H]1O[C@H](O)[C@H](O)[C@H](O)[C@H]1OformulaC6H12O5inchiInChI=1S/C6H12O5/c1-2-3(7)4(8)5(9)6(10)11-2/h2-10H,1H3/t2-,3-,4+,5+,6-/m0/s1inchikeySHZGCJCMOBCMKK-YJRYQGEOSA-Npolar_surface_area90.15refractivity34.38polarizability15.32rotatable_bond_count0acceptor_count5donor_count4physiological_charge0formal_charge0fucose and rhamnose degradationIn E. coli, L-fucose and L-rhamnose are metabolized through parallel pathways. The pathways converge after their corresponding aldolase reactions yielding the same products: lactaldehye. Via reactions catalyzed by proteins encoded in linked operons comprising a regulon, the methylpentose, alpha-L-rhamnopyranose and/or beta-L-rhamnopyranose, is taken into the cell through a proton symporter and metabolized, enabling E. coli to grow on it as a total source of carbon and energy.
For alpha-L-rhamnopyranose, it is isomerized by a l-rhamnose mutarotase resulting in a beta-L-rhamnopyranose which is then isomerized into a keto-L-rhamnulose by a l-rhamnose isomerase. The keto-L-rhamnulose spontaneously changes into a L-rhamnulofuranose which is phosphorylated by a rhamnulokinase resulting in a L-rhamnulose 1-phosphate. This compound reacts with a rhamnulose-1-phosphate aldolase resulting in a dihydroxyacetone phosphate and a lactaldehyde.
For beta-L-rhamnopyranose, it is isomerized by a L-fucose mutarotase resulting in a alpha-L-fucopyranose. This compound is then isomerized by an L-fucose isomerase resulting in a L-fuculose which in turn gets phosphorylated into an L-fuculose 1-phosphate through an L-fuculokinase. The compound L-fuculose 1-phosphate reacts with an L-fuculose phosphate aldolase through a dihydroxyacetone phosphate and a lactaldehyde.
Two pathways can be used for degradation of L-lactaldehyde. Aerobically, it is converted via lactate to pyruvate, also an intermediate of glycolysis. Anaerobically, lactaldehyde reductase is induced which converts lactaldehyde into propane-1,2-diol. Under aerobic conditions, L-lactaldehyde is oxidized in two steps to pyruvate, thereby channeling all the carbons from fucose or rhamnose into central metabolic pathways. Under anaerobic conditions, L-lactaldehyde is reduced to L-1,2-propanediol, which is secreted into the environment.
PW000826MetabolicSpecdb::CMs1084872Specdb::EiMs3466Specdb::NmrOneD311451Specdb::NmrOneD311452Specdb::NmrOneD311453Specdb::NmrOneD311454Specdb::NmrOneD311455Specdb::NmrOneD311456Specdb::NmrOneD311457Specdb::NmrOneD311458Specdb::NmrOneD311459Specdb::NmrOneD311460Specdb::NmrOneD311461Specdb::NmrOneD311462Specdb::NmrOneD311463Specdb::NmrOneD311464Specdb::NmrOneD311465Specdb::NmrOneD311466Specdb::NmrOneD311467Specdb::NmrOneD311468Specdb::NmrOneD311469Specdb::NmrOneD311470Specdb::MsMs27062Specdb::MsMs27063Specdb::MsMs27064Specdb::MsMs33620Specdb::MsMs33621Specdb::MsMs33622439730C0233827586RM4L-rhamnose isomeraseP32170RHAA_ECOLIrhaAhttp://ecmdb.ca/proteins/P32170.xmlL-rhamnose mutarotaseP32156RHAM_ECOLIrhaMhttp://ecmdb.ca/proteins/P32156.xmlalpha-L-Rhamnose > beta-L-Rhamnosealpha-L-Rhamnose <> beta-L-RhamnoseR10819 beta-L-Rhamnose > keto-L-rhamnulose + keto-L-rhamnulosePW_R002968