Disease relevance of mannitol-1-phosphate

• One E. coli strain harboring plasmid pLC15-48 overproduced mannitol-1-phosphate dehydrogenase activity 4- to 5-fold [1].
• Metabolic engineering of mannitol production in Lactococcus lactis: influence of overexpression of mannitol 1-phosphate dehydrogenase in different genetic backgrounds [2].
• Mannitol kinase and mannitol-1-phosphate dehydrogenase activities were detected in two Micromonospora isolates [3].
• Mannitol-1-phosphate dehydrogenase was detected in cell-free extracts of Streptomyces lactamdurans [3].
• To obtain a mannitol-producing Lactococcus lactis strain, the mannitol 1-phosphate dehydrogenase gene (mtlD) from Lactobacillus plantarum was overexpressed in a wild-type strain, a lactate dehydrogenase(LDH)-deficient strain, and a strain with reduced phosphofructokinase activity [2].

High impact information on mannitol-1-phosphate

• A bacterial gene encoding mannitol-1-phosphate dehydrogenase, mtlD, was engineered for expression in higher plants [4].
• We also show that, when incubated with glucose-6-phosphate and mannitol, glucose-6-phosphatase formed mannitol-1-phosphate and that this nonphysiological product was initially present within the microsomes before being released to the medium [5].
• The purified enzyme did not catalyze hydrolysis of mannitol 1-phosphate, a product of both reactions [6].
• Formation of mannitol 1-phosphate in hepatocytes was dependent on the presence of mannitol and was stimulated by compounds that increase the concentration of glucose 6-phosphate [7].
• The major conclusions reported previously were correct, but additionally it is now clear that a C-terminal portion of mannitol-1-phosphate dehydrogenase (the mtlD gene product) exhibits significant sequence identity with an amino-terminal region of human liver fructose-6-phosphate-2-kinase:fructose-2,6-bisphosphatase [8].

Chemical compound and disease context of mannitol-1-phosphate

• A mutant (mtlD) strain of Escherichia coli unable to oxidize mannitol-1-phosphate to fructose-6-phosphate was used to study the fate of mannitol-1-phosphate [9].
• We suggest that the de novo synthesis of mannitol-1-phosphate in E. coli may be a reaction specifically dedicated to the biosynthesis of ribose [9].
• Mannitol-specific phosphoenolpyruvate-dependent phosphotransferase system of Enterococcus faecalis: molecular cloning and nucleotide sequences of the enzyme IIIMtl gene and the mannitol-1-phosphate dehydrogenase gene, expression in Escherichia coli, and comparison of the gene products with similar enzymes [10].

Biological context of mannitol-1-phosphate

• Due to strong inhibition provided by mannitol and mannitol 1-phosphate in the exchange reaction, the kinetics of this reaction cannot be used to determine whether the reaction proceeds via a ping-pong or an ordered reaction mechanism [11].
• The first phosphorylation site, His-554 (P1), was replaced by Ala, which renders the EII-H554A completely inactive in PEP-dependent mannitol phosphorylation, but not in mannitol/mannitol 1-phosphate exchange [12].
• Complementation of an Escherichia coli mtlD mutation with a streptococcal recombinant DNA library allowed isolation of the mannitol-1-phosphate dehydrogenase gene (mtlD) and the adjacent sugar-specific mannitol factor III gene (mtlF) from S. mutans [13].
• This gene has previously been shown (Solomon and Lin, 1972) to be part of an operon, mtl, located at 71 min on the E. coli linkage map containing, in addition to mtlA, the cis-dominant regulatory gene mtlC and mtlD, the structural gene for the enzyme D-mannitol-1-phosphate dehydrogenase [14].
• The Escherichia coli mtl operon, which contains the cis-dominant regulatory region mtlC, the mannitol-specific enzyme II structural gene mtlA, and the D-mannitol-1-phosphate dehydrogenase structural gene mtlD, was cloned into plasmid pBR322 [15].

Anatomical context of mannitol-1-phosphate

• In the presence of enzyme I and HPr of the PTS, and of membranes containing EIIMtl, the phospho group from [(R)-16O,17O,18O]PEP was transferred to D-mannitol to form mannitol 1-phosphate with overall inversion of the configuration at phosphorus with respect to that of PEP [16].
• Transgenic tobacco (Nicotiana tabacum L, cv. SR-1) expressing mannitol 1-phosphate dehydrogenase, MTLD, in chloroplasts and myo-inositol O-methyltransferase, IMT1, in the cytosol after crossing of lines which expressed these foreign genes separately has been analysed [17].

Associations of mannitol-1-phosphate with other chemical compounds

• Two of the plasmids, pLC11-7 and pLC15-48, were shown to contain the mannitol operon, which includes the structural genes for the mannitol-specific enzyme II of the phosphotransferase system and mannitol-1-phosphate dehydrogenase [1].
• Mannitol-1-phosphate dehydrogenase was not detected in isolates of the sanguis species complex, and glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase were absent in species of the mutans complex [18].
• 0. At pH values around neutrality the maximum rate of reduction of fructose-6-phosphate is much higher than that of oxidation of mannitol-1-phosphate [19].
• Enhanced tolerance to salt stress in transgenic loblolly pine simultaneously expressing two genes encoding mannitol-1-phosphate dehydrogenase and glucitol-6-phosphate dehydrogenase [20].

Gene context of mannitol-1-phosphate

• Purification and properties of D-mannitol-1-phosphate dehydrogenase and D-glucitol-6-phosphate dehydrogenase from Escherichia coli [21].
• The cycle is built up to the following enzymes: mannitol 1-phosphate dehydrogenase, mannitol 1-phosphatase, mannitol dehydrogenase and hexokinase [22].
• The MDH of R. sphaeroides Si4 exhibits distant similarity to the mannitol-1-phosphate dehydrogenases from Escherichia coli and Enterococcus faecalis, with 28.1% and 26.3% identity, respectively [23].

Analytical, diagnostic and therapeutic context of mannitol-1-phosphate

• Comparison of secondary structure assignment to sequence alignments suggest the shortest members of this family, mannitol-1-phosphate 5-dehydrogenases, retain core elements but lack secondary structural components found on the surface of pfMDH [24].

References