This view shows enzymes only for those organisms listed below, in the list of taxa known to possess the pathway. If an enzyme name is shown in bold, there is experimental evidence for this enzymatic activity.
|Superclasses:||Biosynthesis → Metabolic Regulators Biosynthesis → Organic Solutes Biosynthesis|
Some taxa known to possess this pathway include : Aeropyrum pernix, Aquifex aeolicus, Archaeoglobus fulgidus, Hyperthermus butylicus, Pyrococcus furiosus, Pyrococcus woesei, Rubrobacter xylanophilus, Thermococcus kodakarensis, Thermotoga maritima
L,L-di-myo-inositol 1,3'-phosphate (also known as di-myo-inositol phosphate, or DIP) is the most widespread organic solute in microorganisms adapted to hot environments. It was first identified in Pyrococcus woesei, in which it is the dominant counterion of K+, which ranges from 500 to 600 mM [Scholz92]. Since then it has been detected in many archaebacteria [Ciulla94, Goncalves03, Lamosa98, Lamosa06, Martins96, Martins97] and some thermophilic bacteria [Empadinhas07]. So far DIP has not been encountered in organisms with optimal growth temperatures below 60°C, and is thus believed to play a role in the thermoprotection of cellular components [Rodrigues07].
The pathway leading to the biosynthesis of L,L-di-myo-inositol 1,3'-phosphate has been described. The pathway consists of four steps - formation of 1D-myo-inositol 3-monophosphate, activation to CDP-1L-myo-inositol, combining the latter with 1D-myo-inositol 3-monophosphate to yield bis(1L-myo-inositol) 3,1'-phosphate 1-phosphate (DIPP), and the dephosphorylation to the final product [Borges06].
In most organisms the enzymes that catalyze the two key steps, activation to CDP-1L-myo-inositol, and formation of bis(1L-myo-inositol) 3,1'-phosphate 1-phosphate, are fused into a single gene. The ipct/dipps gene, encoding the bifubnctional CTP:inositol-1-phosphate cytidylyltransferase/CDP-inositol:inositol-1-phosphate transferase, was identified in the Archaeoglobus fulgidus genome and characterized. The DIPPS domain of that enzyme showed some plasticity in regard to the alcohol-activated donor, and could also accept CDP-glycerol instead of CDP-inositol, leading to production of phosphorylated sn-glycero-3-phospho-1-inositol [Rodrigues07].
Borges06: Borges N, Goncalves LG, Rodrigues MV, Siopa F, Ventura R, Maycock C, Lamosa P, Santos H (2006). "Biosynthetic pathways of inositol and glycerol phosphodiesters used by the hyperthermophile Archaeoglobus fulgidus in stress adaptation." J Bacteriol 188(23);8128-35. PMID: 17028285
Empadinhas07: Empadinhas N, Mendes V, Simoes C, Santos MS, Mingote A, Lamosa P, Santos H, Costa MS (2007). "Organic solutes in Rubrobacter xylanophilus: the first example of di-myo-inositol-phosphate in a thermophile." Extremophiles 11(5);667-73. PMID: 17510735
Goncalves03: Goncalves LG, Huber R, da Costa MS, Santos H (2003). "A variant of the hyperthermophile Archaeoglobus fulgidus adapted to grow at high salinity." FEMS Microbiol Lett 218(2);239-44. PMID: 12586398
Lamosa06: Lamosa P, Goncalves LG, Rodrigues MV, Martins LO, Raven ND, Santos H (2006). "Occurrence of 1-glyceryl-1-myo-inosityl phosphate in hyperthermophiles." Appl Environ Microbiol 72(9);6169-73. PMID: 16957243
Lamosa98: Lamosa P, Martins LO, Da Costa MS , Santos H (1998). "Effects of temperature, salinity, and medium composition on compatible solute accumulation by thermococcus spp." Appl Environ Microbiol 64(10);3591-8. PMID: 9758772
Martins96: Martins LO, Carreto LS, Da Costa MS, Santos H (1996). "New compatible solutes related to Di-myo-inositol-phosphate in members of the order Thermotogales." J Bacteriol 178(19);5644-51. PMID: 8824608
Rodrigues07: Rodrigues MV, Borges N, Henriques M, Lamosa P, Ventura R, Fernandes C, Empadinhas N, Maycock C, da Costa MS, Santos H (2007). "Bifunctional CTP:inositol-1-phosphate cytidylyltransferase/CDP-inositol:inositol-1-phosphate transferase, the key enzyme for di-myo-inositol-phosphate synthesis in several (hyper)thermophiles." J Bacteriol 189(15);5405-12. PMID: 17526717
Bachhawat99: Bachhawat N, Mande SC (1999). "Identification of the INO1 gene of Mycobacterium tuberculosis H37Rv reveals a novel class of inositol-1-phosphate synthase enzyme." J Mol Biol 291(3);531-6. PMID: 10448034
Fischbach06: Fischbach A, Adelt S, Muller A, Vogel G (2006). "Disruption of inositol biosynthesis through targeted mutagenesis in Dictyostelium discoideum: generation and characterization of inositol-auxotrophic mutants." Biochem J 397(3);509-18. PMID: 16599905
Norman02: Norman RA, McAlister MS, Murray-Rust J, Movahedzadeh F, Stoker NG, McDonald NQ (2002). "Crystal structure of inositol 1-phosphate synthase from Mycobacterium tuberculosis, a key enzyme in phosphatidylinositol synthesis." Structure (Camb) 10(3);393-402. PMID: 12005437
Shukla04: Shukla S, VanToai TT, Pratt RC (2004). "Expression and nucleotide sequence of an INS (3) P1 synthase gene associated with low-phytate kernels in maize (Zea mays L.)." J Agric Food Chem 52(14);4565-70. PMID: 15237968
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