Browsing Pathways

Diacetylchitobiose (also known as N,N'-diacetylchitobiose and chitobiose) is a sole source of carbon for E.coli. PTS system mannitol-specific EIICBA component facilitates the imports of diacetylchitobiose as well as the phosphorylation to diacetylchitobiose 6'-phosphate. Later on, diacetylchitobiose 6'-phosphate is hydrolyzed to N-monoacetylchitobiose 6'-phosphate, which also produce acetic acid. N-monoacetylchitobiose 6'-phosphate undergoes further hydrolyzation to form N-Acetyl-D-Glucosamine 6-Phosphate and glucosamine by monoacetylchitobiose-6-phosphate hydrolase.

This pathway demonstrates the biosynthesis of tetrahydromonapterin in E.coli. However, it is still unclear about biological role of tetrahydromonapterin. GTP cyclohydrolase 1 generates formic acid and 7,8-dihydroneopterin 3'-triphosphate with cofactor GTP and water. 7,8-dihydroneopterin 3'-triphosphate is converted to dihydromonapterin-triphosphate by d-erythro-7,8-dihydroneopterin triphosphate epimerase (folX). Later, dihydromonapterin-triphosphate is hydroxylated to dihydromethysticin, and eventually form tetrahydromonapterin via dihydromonapterin reductase (folM) with cofactor NADPH.

Aminopropylcadaverine, a polyamine, is the final product of aminopropylcadaverine biosynthesis pathway. Polyamines are involved in protein synthesis, DNA and RNA related processes, as well as the facilitation of cell stress resistance and membrane integrity; therefore polyamines are essential for cell growth. In this pathway, L-lysine is produced by lysine biosynthesis, then lysine decarboxylase will convert L-lysine into cadaverine. In the final step, spermidine synthase will catalyze cadaverine and decarboxy-SAM to aminopropylcadaverine as well as 5'-Methylthioadenosine.

Uracil is a pyrimidine nucleobase found in RNA, and can be used as a source of nitrogen for E. coli. There are at least three pathways through which uracil is degraded. This one begins with uracil, which originates from purine degradation. The putative monooxygenase enzyme rutA catalyzes the breakdown of uracil into peroxyaminoacrylate, using FMNH2 as a cofactor. Peroxyaminoacrylate is then broken down into both carbamic acid and 3-aminoacrylate following the addition of a water molecule by the putative isochorismatase family protein rutB. Carbamic acid can then spontaneously, with the addition of a hydrogen ion, split into an ammonium ion and a molecule of carbon dioxide. 3-aminoacrylate, on the other hand, is catalyzed by the UPF0076 protein rutC to form 2-aminoacrylic acid. This compound enters into a reaction catalyzed by protein rutD, which adds a water molecule and hydrogen ion and forms malonic semialdehyde with ammonium being a byproduct. Finally, the putative NADH dehydrogenase/NAD(P)H nitroreductase rutE complex converts malonic semialdehyde into hydroxypropionic acid, which is then used to form other necessary chemicals. The ammonium ions produced will be the important source of nitrogen for the bacteria.

Aminopropylcadaverine, a polyamine, is the final product of aminopropylcadaverine biosynthesis pathway. Polyamines are involved in protein synthesis, DNA and RNA related processes, as well as the facilitation of cell stress resistance and membrane integrity; therefore polyamines are essential for cell growth. In this pathway, L-lysine is produced by lysine biosynthesis, then lysine decarboxylase will convert L-lysine into cadaverine. In the final step, spermidine synthase will catalyze cadaverine and decarboxy-SAM to aminopropylcadaverine as well as 5'-Methylthioadenosine.

Diacetylchitobiose (also known as N,N'-diacetylchitobiose and chitobiose) is a sole source of carbon for E.coli. PTS system mannitol-specific EIICBA component facilitates the imports of diacetylchitobiose as well as the phosphorylation to diacetylchitobiose 6'-phosphate. Later on, diacetylchitobiose 6'-phosphate is hydrolyzed to N-monoacetylchitobiose 6'-phosphate, which also produce acetic acid. N-monoacetylchitobiose 6'-phosphate undergoes further hydrolyzation to form N-Acetyl-D-Glucosamine 6-Phosphate and glucosamine by monoacetylchitobiose-6-phosphate hydrolase.

The process of phenylethylamine metabolism starts with 2-phenylethylamine interacting with an oxygen molecule and a water molecule in the periplasmic space through a phenylethylamine oxidase. This reaction results in the release of a hydrogen peroxide, ammonium and phenylacetaldehyde. Phenylacetaldehyde is introduced into the cytosol and degraded into phenylacetate by reaction with a phenylacetaldehyde dehydrogenase. This reaction involves phenylacetaldehyde interacting with NAD, and a water molecule and then resulting in the release of NADH, and 2 hydrogen ion. Phenylacetate is then degraded. The first step involves phenylacetate interacting with an coenzyme A and an ATP driven phenylacetate-CoA ligase resulting in the release of a AMP, a diphosphate and a phenylacetyl-CoA. This resulting compound the interacts with a hydrogen ion, NADPH, and oxygen molecule through a ring 1,2-phenylacetyl-CoA epoxidase protein complex resulting in the release of a water molecule, an NADP and a 2-(1,2-epoxy-1,2-dihydrophenyl)acetyl-CoA. This compound is then metabolized by a ring 1,2 epoxyphenylacetyl-CoA isomerase resulting in a 2-oxepin-2(3H)-ylideneacetyl-CoA. This compound is then hydrolated through a oxepin-CoA hydrolase resulting in a 3-oxo-5,6-didehydrosuberyl-CoA semialdehyde. This commpound then interacts with a water molecule and NADP driven 3-oxo-5,6-dehydrosuberyl-CoA semialadehyde dehydrogenase resulting in 2 hydrogen ions, a NADPH and a 3-oxo-5,6-didehydrosuberyl-CoA. The resulting compound interacts with a coenzyme A and a 3-oxo-5,6 dehydrosuberyl-CoA thiolase resulting in an acetyl-CoA and a 2,3-didehydroadipyl-CoA. This resulting compound is the hydrated by a 2,3-dehydroadipyl-CoA hydratas resulting in a 3-hydroxyadipyl-CoA whuch is dehydrogenated through an NAD driven 3-hydroxyadipyl-CoA dehydrogenase resulting in a NADH, a hydrogen ion and a 3-oxoadipyl-CoA. The latter compound then interacts with conezyme A through a beta-ketoadipyl-CoA thiolase resulting in an acetyl-CoA and a succinyl-CoA. The succinyl-CoA is then integrated into the TCA cycle.

The process of phenylethylamine metabolism starts with 2-phenylethylamine interacting with an oxygen molecule and a water molecule in the periplasmic space through a phenylethylamine oxidase. This reaction results in the release of a hydrogen peroxide, ammonium and phenylacetaldehyde. Phenylacetaldehyde is introduced into the cytosol and degraded into phenylacetate by reaction with a phenylacetaldehyde dehydrogenase. This reaction involves phenylacetaldehyde interacting with NAD, and a water molecule and then resulting in the release of NADH, and 2 hydrogen ion. Phenylacetate is then degraded. The first step involves phenylacetate interacting with an coenzyme A and an ATP driven phenylacetate-CoA ligase resulting in the release of a AMP, a diphosphate and a phenylacetyl-CoA. This resulting compound the interacts with a hydrogen ion, NADPH, and oxygen molecule through a ring 1,2-phenylacetyl-CoA epoxidase protein complex resulting in the release of a water molecule, an NADP and a 2-(1,2-epoxy-1,2-dihydrophenyl)acetyl-CoA. This compound is then metabolized by a ring 1,2 epoxyphenylacetyl-CoA isomerase resulting in a 2-oxepin-2(3H)-ylideneacetyl-CoA. This compound is then hydrolated through a oxepin-CoA hydrolase resulting in a 3-oxo-5,6-didehydrosuberyl-CoA semialdehyde. This commpound then interacts with a water molecule and NADP driven 3-oxo-5,6-dehydrosuberyl-CoA semialadehyde dehydrogenase resulting in 2 hydrogen ions, a NADPH and a 3-oxo-5,6-didehydrosuberyl-CoA. The resulting compound interacts with a coenzyme A and a 3-oxo-5,6 dehydrosuberyl-CoA thiolase resulting in an acetyl-CoA and a 2,3-didehydroadipyl-CoA. This resulting compound is the hydrated by a 2,3-dehydroadipyl-CoA hydratas resulting in a 3-hydroxyadipyl-CoA whuch is dehydrogenated through an NAD driven 3-hydroxyadipyl-CoA dehydrogenase resulting in a NADH, a hydrogen ion and a 3-oxoadipyl-CoA. The latter compound then interacts with conezyme A through a beta-ketoadipyl-CoA thiolase resulting in an acetyl-CoA and a succinyl-CoA. The succinyl-CoA is then integrated into the TCA cycle.

This pathway demonstrate the biosynthesis of thiazole moiety in E.coli K-12 strain and Salmonella enterica serovar Typhimurium. L-Tyrosine is generated from tyrosine biosynthesis. With S-Adenosylmethionine and NADPH, L-Tyrosine can be catalyzed into four different small molecules: 4-methylcatechol, dehydroglycine, 5'-deoxyadenosine and L-methionine as well as NADP by dehydroglycine synthase (encoded by thiH gene). Meanwhile, 1-deoxyxylulose-5-phosphate synthase (encoded by dxs gene) catalyzes pyruvic acid and D-Glyceraldehyde 3-phosphate into 1-Deoxy-D-xylulose 5-phosphate. The final reaction of the pathway is facilitated by thiazole synthase (encoded by thiG and thiH), which require a thiocarboxy-[ThiS-Protein], 1-deoxy-D-xylulose 5-phosphate and 2-iminoacetate to form 2-((2R,5Z)-2-Carboxy-4-methylthiazol-5(2H)-ylidene)ethyl phosphate for Thiamin Diphosphate Biosynthesis, as well as a ThiS sulfur-carrier protein and water.

Aminopropylcadaverine, a polyamine, is the final product of aminopropylcadaverine biosynthesis pathway. Polyamines are involved in protein synthesis, DNA and RNA related processes, as well as the facilitation of cell stress resistance and membrane integrity; therefore polyamines are essential for cell growth. In this pathway, L-lysine is produced by lysine biosynthesis, then lysine decarboxylase will convert L-lysine into cadaverine. In the final step, spermidine synthase will catalyze cadaverine and decarboxy-SAM to aminopropylcadaverine as well as 5'-Methylthioadenosine.