Browsing Pathways

L-Glutamine is transported into the cytoplasm through a glutamine ABC transporter. Once inside, L-glutamine is metabolized with glutaminase to produce an L-glutamic acid. This process can be reversed through a glutamine synthetase resulting in L-glutamine. L-glutamic acid can also be transported into the cytoplasm through various methods: a glutamate/aspartate:H+ symporter GltP, a glutamate:sodium symporter, or a glutamate/aspartate ABC transporter. L-Glutamic acid can proceed to L-glutamate metabolism or it can undergo a reversible reaction through a glutamate racemase resulting in D-glutamic acid. This compound can also be obtained from D-glutamine interacting with a glutaminase. D-Glutamic acid reacts with UDP-N-acetylmuramoyl-L-alanine through an ATP-driven UDP-N-acetylmuramoylalanine-D-glutamate ligase resulting in a UDP-N-acetylmuramoyl-L-alanyl-D-glutamate which is then integrated into peptidoglycan biosynthesis. UDP-N-acetylmuramoyl-L-alanine comes from the amino sugar and nucleotide sugar metabolism product, UDP-N-acetylmuraminate which reacts with L-alanine through an ATP-driven UDP-N-acetylmuramate-L-alanine ligase.

Lipoic acid metabolism starts with caprylic acid being introduced into the cytoplasm, however, no transporter has been identified yet. i) Once caprylic acid is in the cytoplasm, it can react with a holo-acp through an ATP-driven 2-acylglycerophosphoethanolamine acyltransferase/acyl-ACP synthetase resulting in pyrophosphate, AMP, and octanoyl-[acp]. The latter compound can also be obtained from palmitate biosynthesis. ii) Octanoyl-acp then interacts with a lipoyl-carrier protein L-lysine through an octanoyltransferase resulting in a hydrogen ion, a holo-acyl-acp, and an N6-(octanoyl)lysine. iii) N6-(octanoyl)lysine reacts with an S-adenosylmethionine, a sulfurated[sulfur carrier], and a reduced ferredoxin through a lipoate-protein ligase A, resulting in a 5-deoxyadenosine, an L-methionine, an unsulfurated [sulfur carrier], oxidized ferredoxin, and protein N6-(octanoyl)lysine. Caprylic acid can also interact with ATP and a lipoyl-carrier protein-L-lysine through a lipoate-protein ligase A resulting in an AMP, pyrophosphate, hydrogen ion, and protein N6-(octanoyl)lysine. The latter compound reacts with an S-adenosylmethionine, a sulfurated[sulfur carrier] and a reduced ferredoxin through a lipoate-protein ligase A, resulting in a 5-deoxyadenosine, an L-methionine, an unsulfurated [sulfur carrier], oxidized ferredoxin, and a protein N6-(octanoyl)lysine. R-Lipoic acid can be absorbed from the environment, as seen in studies by Morris TW. In this pathway, the lipoyl-protein ligase LplA utilizes pre-existing lipoate that has been imported from outside the cell, and thus catalyzes a salvage pathway. Lipoic acid interacts with ATP and hydrogen ion through a lipoyl-protein ligase A, resulting in a pyrophosphate and a lipoyl-AMP (lipoyl-adenylate). This compound then interacts with a lipoyl-carrier protein-L-lysine through a lipoate-protein ligase A resulting in an AMP, a hydrogen ion, and a protein N6-(lipoyl) lysine. It has been suggested that the conversion of octanoylated-domains into lipoylated ones described in this pathway may be a type of a repair pathway, activated only if the other lipoate biosynthetic pathways are malfunctioning.

Lipoic acid metabolism starts with caprylic acid being introduced into the cytoplasm, however, no transporter has been identified yet. i) Once caprylic acid is in the cytoplasm, it can react with a holo-acp through an ATP-driven 2-acylglycerophosphoethanolamine acyltransferase/acyl-ACP synthetase resulting in pyrophosphate, AMP, and octanoyl-[acp]. The latter compound can also be obtained from palmitate biosynthesis. ii) Octanoyl-acp then interacts with a lipoyl-carrier protein L-lysine through an octanoyltransferase resulting in a hydrogen ion, a holo-acyl-acp, and an N6-(octanoyl)lysine. iii) N6-(octanoyl)lysine reacts with an S-adenosylmethionine, a sulfurated[sulfur carrier], and a reduced ferredoxin through a lipoate-protein ligase A, resulting in a 5-deoxyadenosine, an L-methionine, an unsulfurated [sulfur carrier], oxidized ferredoxin, and protein N6-(octanoyl)lysine. Caprylic acid can also interact with ATP and a lipoyl-carrier protein-L-lysine through a lipoate-protein ligase A resulting in an AMP, pyrophosphate, hydrogen ion, and protein N6-(octanoyl)lysine. The latter compound reacts with an S-adenosylmethionine, a sulfurated[sulfur carrier] and a reduced ferredoxin through a lipoate-protein ligase A, resulting in a 5-deoxyadenosine, an L-methionine, an unsulfurated [sulfur carrier], oxidized ferredoxin, and a protein N6-(octanoyl)lysine. R-Lipoic acid can be absorbed from the environment, as seen in studies by Morris TW. In this pathway, the lipoyl-protein ligase LplA utilizes pre-existing lipoate that has been imported from outside the cell, and thus catalyzes a salvage pathway. Lipoic acid interacts with ATP and hydrogen ion through a lipoyl-protein ligase A, resulting in a pyrophosphate and a lipoyl-AMP (lipoyl-adenylate). This compound then interacts with a lipoyl-carrier protein-L-lysine through a lipoate-protein ligase A resulting in an AMP, a hydrogen ion, and a protein N6-(lipoyl) lysine. It has been suggested that the conversion of octanoylated-domains into lipoylated ones described in this pathway may be a type of a repair pathway, activated only if the other lipoate biosynthetic pathways are malfunctioning.

Taurine enters into the cytoplasm through a taurine ATP-binding cassette (ABC) transporters. Once inside, the enzyme taurine dioxygenase encourages the interaction between taurine, oxoglutaric acid and oxygen resulting in the release of succinic acid, sulfite, aminoacetaldehyde, and carbon dioxide.

Lysine is an essential amino acid used in protein synthesis. Lysine can be transported into the cell by probable cadaverine (also known as lysine antiporter). Once inside the cell, lysine is decarboxylated by lysine decarboxylase to cadaverine. Cadaverine can then exit the cell via the same type of transporter as lysine (probable cadaverine). Alternatively, lysine can be produced during lysine biosynthesis (from aspartic acid) inside the cell and used in the same pathway.

Lysine is an essential amino acid used in protein synthesis. Lysine can be transported into the cell by probable cadaverine (also known as lysine antiporter). Once inside the cell, lysine is decarboxylated by lysine decarboxylase to cadaverine. Cadaverine can then exit the cell via the same type of transporter as lysine (probable cadaverine). Alternatively, lysine can be produced during lysine biosynthesis (from aspartic acid) inside the cell and used in the same pathway.

L-Glutamine is transported into the cytoplasm through a glutamine ABC transporter. Once inside, L-glutamine is metabolized with glutaminase to produce an L-glutamic acid. This process can be reversed through a glutamine synthetase resulting in L-glutamine. L-glutamic acid can also be transported into the cytoplasm through various methods: a glutamate/aspartate:H+ symporter GltP, a glutamate:sodium symporter, or a glutamate/aspartate ABC transporter. L-Glutamic acid can proceed to L-glutamate metabolism or it can undergo a reversible reaction through a glutamate racemase resulting in D-glutamic acid. This compound can also be obtained from D-glutamine interacting with a glutaminase. D-Glutamic acid reacts with UDP-N-acetylmuramoyl-L-alanine through an ATP-driven UDP-N-acetylmuramoylalanine-D-glutamate ligase resulting in a UDP-N-acetylmuramoyl-L-alanyl-D-glutamate which is then integrated into peptidoglycan biosynthesis. UDP-N-acetylmuramoyl-L-alanine comes from the amino sugar and nucleotide sugar metabolism product, UDP-N-acetylmuraminate which reacts with L-alanine through an ATP-driven UDP-N-acetylmuramate-L-alanine ligase.

L-Glutamine is transported into the cytoplasm through a glutamine ABC transporter. Once inside, L-glutamine is metabolized with glutaminase to produce an L-glutamic acid. This process can be reversed through a glutamine synthetase resulting in L-glutamine. L-glutamic acid can also be transported into the cytoplasm through various methods: a glutamate/aspartate:H+ symporter GltP, a glutamate:sodium symporter, or a glutamate/aspartate ABC transporter. L-Glutamic acid can proceed to L-glutamate metabolism or it can undergo a reversible reaction through a glutamate racemase resulting in D-glutamic acid. This compound can also be obtained from D-glutamine interacting with a glutaminase. D-Glutamic acid reacts with UDP-N-acetylmuramoyl-L-alanine through an ATP-driven UDP-N-acetylmuramoylalanine-D-glutamate ligase resulting in a UDP-N-acetylmuramoyl-L-alanyl-D-glutamate which is then integrated into peptidoglycan biosynthesis. UDP-N-acetylmuramoyl-L-alanine comes from the amino sugar and nucleotide sugar metabolism product, UDP-N-acetylmuraminate which reacts with L-alanine through an ATP-driven UDP-N-acetylmuramate-L-alanine ligase.

Taurine enters into the cytoplasm through a taurine ATP-binding cassette (ABC) transporters. Once inside, the enzyme taurine dioxygenase encourages the interaction between taurine, oxoglutaric acid and oxygen resulting in the release of succinic acid, sulfite, aminoacetaldehyde, and carbon dioxide.

Lipoic acid metabolism starts with caprylic acid being introduced into the cytoplasm, however, no transporter has been identified yet. i) Once caprylic acid is in the cytoplasm, it can react with a holo-acp through an ATP-driven 2-acylglycerophosphoethanolamine acyltransferase/acyl-ACP synthetase resulting in pyrophosphate, AMP, and octanoyl-[acp]. The latter compound can also be obtained from palmitate biosynthesis. ii) Octanoyl-acp then interacts with a lipoyl-carrier protein L-lysine through an octanoyltransferase resulting in a hydrogen ion, a holo-acyl-acp, and an N6-(octanoyl)lysine. iii) N6-(octanoyl)lysine reacts with an S-adenosylmethionine, a sulfurated[sulfur carrier], and a reduced ferredoxin through a lipoate-protein ligase A, resulting in a 5-deoxyadenosine, an L-methionine, an unsulfurated [sulfur carrier], oxidized ferredoxin, and protein N6-(octanoyl)lysine. Caprylic acid can also interact with ATP and a lipoyl-carrier protein-L-lysine through a lipoate-protein ligase A resulting in an AMP, pyrophosphate, hydrogen ion, and protein N6-(octanoyl)lysine. The latter compound reacts with an S-adenosylmethionine, a sulfurated[sulfur carrier] and a reduced ferredoxin through a lipoate-protein ligase A, resulting in a 5-deoxyadenosine, an L-methionine, an unsulfurated [sulfur carrier], oxidized ferredoxin, and a protein N6-(octanoyl)lysine. R-Lipoic acid can be absorbed from the environment, as seen in studies by Morris TW. In this pathway, the lipoyl-protein ligase LplA utilizes pre-existing lipoate that has been imported from outside the cell, and thus catalyzes a salvage pathway. Lipoic acid interacts with ATP and hydrogen ion through a lipoyl-protein ligase A, resulting in a pyrophosphate and a lipoyl-AMP (lipoyl-adenylate). This compound then interacts with a lipoyl-carrier protein-L-lysine through a lipoate-protein ligase A resulting in an AMP, a hydrogen ion, and a protein N6-(lipoyl) lysine. It has been suggested that the conversion of octanoylated-domains into lipoylated ones described in this pathway may be a type of a repair pathway, activated only if the other lipoate biosynthetic pathways are malfunctioning.