Browsing Pathways

The citrate lyase activation starts with a 3-dephospho-CoA reacting with ATP and a hydrogen ion through a triphosphoribosyl-dephospho-CoA synthase resulting in a adenine and a 2'-(5'-triphospho-alpha-D-ribosyl)-3'-dephospho-CoA. The latter compound in turn reacts with with a citrate lyase acyl-carrier protein through a apo-citrate lyase phosphoribosyl-dephospho-CoA transferase resulting in the release of a pyrophosphate and a hydrogen ion and a holo citrate lyase acyl-carrier protein.This protein complex can either react with a hydrogen ion and a acetate resulting in the release of a water and an acetyl-holo citrate lyase acyl-carrier protein. The holo acyl-carrier protein creacts with an ATP and an acetate through a citrate lyase synthase resulting in the release of an AMP, a pyrophosphate and an acetyl-holo citrate lyase acyl-ccarrier protein. The holo citrate lyase acyl-carrier protein can also interact with an S-acetyl phosphopantethiene resulting in the release of a 4-phosphopantethiene and an acetyl-holo citrate lyase acyl-carrier protein.

The citrate lyase activation starts with a 3-dephospho-CoA reacting with ATP and a hydrogen ion through a triphosphoribosyl-dephospho-CoA synthase resulting in a adenine and a 2'-(5'-triphospho-alpha-D-ribosyl)-3'-dephospho-CoA. The latter compound in turn reacts with with a citrate lyase acyl-carrier protein through a apo-citrate lyase phosphoribosyl-dephospho-CoA transferase resulting in the release of a pyrophosphate and a hydrogen ion and a holo citrate lyase acyl-carrier protein.This protein complex can either react with a hydrogen ion and a acetate resulting in the release of a water and an acetyl-holo citrate lyase acyl-carrier protein. The holo acyl-carrier protein creacts with an ATP and an acetate through a citrate lyase synthase resulting in the release of an AMP, a pyrophosphate and an acetyl-holo citrate lyase acyl-ccarrier protein. The holo citrate lyase acyl-carrier protein can also interact with an S-acetyl phosphopantethiene resulting in the release of a 4-phosphopantethiene and an acetyl-holo citrate lyase acyl-carrier protein.

The citrate lyase activation starts with a 3-dephospho-CoA reacting with ATP and a hydrogen ion through a triphosphoribosyl-dephospho-CoA synthase resulting in a adenine and a 2'-(5'-triphospho-alpha-D-ribosyl)-3'-dephospho-CoA. The latter compound in turn reacts with with a citrate lyase acyl-carrier protein through a apo-citrate lyase phosphoribosyl-dephospho-CoA transferase resulting in the release of a pyrophosphate and a hydrogen ion and a holo citrate lyase acyl-carrier protein.This protein complex can either react with a hydrogen ion and a acetate resulting in the release of a water and an acetyl-holo citrate lyase acyl-carrier protein. The holo acyl-carrier protein creacts with an ATP and an acetate through a citrate lyase synthase resulting in the release of an AMP, a pyrophosphate and an acetyl-holo citrate lyase acyl-ccarrier protein. The holo citrate lyase acyl-carrier protein can also interact with an S-acetyl phosphopantethiene resulting in the release of a 4-phosphopantethiene and an acetyl-holo citrate lyase acyl-carrier protein.

Purine ribonucleoside degradation leads to the production of alpha-D-ribose-1-phosphate. Xanthosine is transported into the cytosol through a xapB. Once in the cytosol xanthosine interacts with phosphate through a xanthosine phosphorylase resulting in the release of a xanthine and a alpha-D-ribose-1-phosphate. Adenosine is transported through a nupC or a nupG transporter, once inside the cytosol it can either react with a phosphate through a adenosine phosphorylase resultin in the release of a adenine and an alpha-D-ribose-1-phosphate. Adenosine reacts with water and hydrogen ion through a adenosine deaminase resulting in the release of ammonium and inosine. Inosine reacts with phosphate through a inosine phosphorylase resulting in the release of a hypoxanthine and an alpha-D-ribose-1-phosphate. Guanosine reacts with a phosphate through a guanosine phosphorylase resulting in the release of a guanine and a alpha-D-ribose-1-phosphate.

Lipopolysaccharide (LPS) is a major component of outer membrane which is consisted of lipid A-core (oligosaccharide) on both inner and outer region and O-antigen (known as distal repeating unit with four sugars: N-acetylglucosamine, glucose, rhamnose and galactose). O-antigen is part of three domains of LPS, which is attached to lipid A-core; however, O-antigen and lipid A-core are synthesized separately. In this pathway, synthesis of three of O-antigen sugars is demonstrated. UDP-α-D-galactose is converted to UDP-D-Galacto-1,4-furanose by facilitation of UDP-galactopyranose mutase. dTTP glucose-1-phosphate is derivatized to dTDP-rhamnose. Fructose-6-phosphate gains an amino group, incorporates an acetate moiety and then acquires a nucleoside diphosphate resulting in UDP-N-acetyl-D-glucosamine.

Guanosine can be converted into guanine through a phosphate driven guanosine phosphorylase resulting in the release of an alpha-D-ribose 1 phosphate and a guanine. This compound in turn reacts with a PRPP through a guanine phosphoribosyltransferase resulting in the release of a pyrophosphate and a GMP. Guanosine can also react with and ATP driven guanosine kinase resulting in the release of an ADP, s hydrogen ion and a GMP

Cardiolipin (CL) is an important component of the inner mitochondrial membrane where it constitutes about 20% of the total lipid composition. It is essential for the optimal function of numerous enzymes that are involved in mitochondrial energy metabolism (Wikipedia). Cardiolipin biosynthesis occurs mainly in the mitochondria, but there also exists an alternative synthesis route for CDP-diacylglycerol that takes place in the endoplasmic reticulum. This second route may supplement this pathway. All membrane-localized enzymes are coloured dark green in the image. First, dihydroxyacetone phosphate (or glycerone phosphate) from glycolysis is used by the cytosolic enzyme glycerol-3-phosphate dehydrogenase [NAD(+)] to synthesize sn-glycerol 3-phosphate. Second, the mitochondrial outer membrane enzyme glycerol-3-phosphate acyltransferase esterifies an acyl-group to the sn-1 position of sn-glycerol 3-phosphate to form 1-acyl-sn-glycerol 3-phosphate (lysophosphatidic acid or LPA). Third, the enzyme 1-acyl-sn-glycerol-3-phosphate acyltransferase converts LPA into phosphatidic acid (PA or 1,2-diacyl-sn-glycerol 3-phosphate) by esterifying an acyl-group to the sn-2 position of the glycerol backbone. PA is then transferred to the inner mitochondrial membrane to continue cardiolipin synthesis. Fourth, magnesium-dependent phosphatidate cytidylyltransferase catalyzes the conversion of PA into CDP-diacylglycerol. Fifth, CDP-diacylglycerol--glycerol-3-phosphate 3-phosphatidyltransferase synthesizes phosphatidylglycerophosphate (PGP). Sixth, phosphatidylglycerophosphatase and protein-tyrosine phosphatase dephosphorylates PGP to form phosphatidylglycerol (PG). Last, cardiolipin synthase catalyzes the synthesis of cardiolipin by transferring a phosphatidyl group from a second CDP-diacylglycerol to PG. It requires a divalent metal cation cofactor.

Cardiolipin (CL) is an important component of the inner mitochondrial membrane where it constitutes about 20% of the total lipid composition. It is essential for the optimal function of numerous enzymes that are involved in mitochondrial energy metabolism (Wikipedia). Cardiolipin biosynthesis occurs mainly in the mitochondria, but there also exists an alternative synthesis route for CDP-diacylglycerol that takes place in the endoplasmic reticulum. This second route may supplement this pathway. All membrane-localized enzymes are coloured dark green in the image. First, dihydroxyacetone phosphate (or glycerone phosphate) from glycolysis is used by the cytosolic enzyme glycerol-3-phosphate dehydrogenase [NAD(+)] to synthesize sn-glycerol 3-phosphate. Second, the mitochondrial outer membrane enzyme glycerol-3-phosphate acyltransferase esterifies an acyl-group to the sn-1 position of sn-glycerol 3-phosphate to form 1-acyl-sn-glycerol 3-phosphate (lysophosphatidic acid or LPA). Third, the enzyme 1-acyl-sn-glycerol-3-phosphate acyltransferase converts LPA into phosphatidic acid (PA or 1,2-diacyl-sn-glycerol 3-phosphate) by esterifying an acyl-group to the sn-2 position of the glycerol backbone. PA is then transferred to the inner mitochondrial membrane to continue cardiolipin synthesis. Fourth, magnesium-dependent phosphatidate cytidylyltransferase catalyzes the conversion of PA into CDP-diacylglycerol. Fifth, CDP-diacylglycerol--glycerol-3-phosphate 3-phosphatidyltransferase synthesizes phosphatidylglycerophosphate (PGP). Sixth, phosphatidylglycerophosphatase and protein-tyrosine phosphatase dephosphorylates PGP to form phosphatidylglycerol (PG). Last, cardiolipin synthase catalyzes the synthesis of cardiolipin by transferring a phosphatidyl group from a second CDP-diacylglycerol to PG. It requires a divalent metal cation cofactor.

Cardiolipin (CL) is an important component of the inner mitochondrial membrane where it constitutes about 20% of the total lipid composition. It is essential for the optimal function of numerous enzymes that are involved in mitochondrial energy metabolism (Wikipedia). Cardiolipin biosynthesis occurs mainly in the mitochondria, but there also exists an alternative synthesis route for CDP-diacylglycerol that takes place in the endoplasmic reticulum. This second route may supplement this pathway. All membrane-localized enzymes are coloured dark green in the image. First, dihydroxyacetone phosphate (or glycerone phosphate) from glycolysis is used by the cytosolic enzyme glycerol-3-phosphate dehydrogenase [NAD(+)] to synthesize sn-glycerol 3-phosphate. Second, the mitochondrial outer membrane enzyme glycerol-3-phosphate acyltransferase esterifies an acyl-group to the sn-1 position of sn-glycerol 3-phosphate to form 1-acyl-sn-glycerol 3-phosphate (lysophosphatidic acid or LPA). Third, the enzyme 1-acyl-sn-glycerol-3-phosphate acyltransferase converts LPA into phosphatidic acid (PA or 1,2-diacyl-sn-glycerol 3-phosphate) by esterifying an acyl-group to the sn-2 position of the glycerol backbone. PA is then transferred to the inner mitochondrial membrane to continue cardiolipin synthesis. Fourth, magnesium-dependent phosphatidate cytidylyltransferase catalyzes the conversion of PA into CDP-diacylglycerol. Fifth, CDP-diacylglycerol--glycerol-3-phosphate 3-phosphatidyltransferase synthesizes phosphatidylglycerophosphate (PGP). Sixth, phosphatidylglycerophosphatase and protein-tyrosine phosphatase dephosphorylates PGP to form phosphatidylglycerol (PG). Last, cardiolipin synthase catalyzes the synthesis of cardiolipin by transferring a phosphatidyl group from a second CDP-diacylglycerol to PG. It requires a divalent metal cation cofactor.

The citrate lyase activation starts with a 3-dephospho-CoA reacting with ATP and a hydrogen ion through a triphosphoribosyl-dephospho-CoA synthase resulting in a adenine and a 2'-(5'-triphospho-alpha-D-ribosyl)-3'-dephospho-CoA. The latter compound in turn reacts with with a citrate lyase acyl-carrier protein through a apo-citrate lyase phosphoribosyl-dephospho-CoA transferase resulting in the release of a pyrophosphate and a hydrogen ion and a holo citrate lyase acyl-carrier protein.This protein complex can either react with a hydrogen ion and a acetate resulting in the release of a water and an acetyl-holo citrate lyase acyl-carrier protein. The holo acyl-carrier protein creacts with an ATP and an acetate through a citrate lyase synthase resulting in the release of an AMP, a pyrophosphate and an acetyl-holo citrate lyase acyl-ccarrier protein. The holo citrate lyase acyl-carrier protein can also interact with an S-acetyl phosphopantethiene resulting in the release of a 4-phosphopantethiene and an acetyl-holo citrate lyase acyl-carrier protein.