Cis-trans isomerase

Takahashi, N., Hayano, T., Suzuki, M. Peptidyl-prolyl cis-trans isomerase is the cyclosporin A binding protein cyclophilin. Nature 337 473-475, 1989. 

Junker F, JL Ramos (1999) Involvement of the cis/trans isomerase Cti in solvent resistance of Pseudomonas putida DOT-TIE. J Bacterial 181 5693-5700. 

Peptidyl-prolyl cis-trans isomerase A (Rotamase) P05092 3X 2X... 

These catalysts facilitate the interconversion of isomeric compounds and include racemases, optimerases, cis-trans isomerases, intramolecular oxidoreductases and intramolecular transferases. Scheme 10.14 shows the conversion of an aldehyde to a ketone by triose phosphate isomerase. 

Peptidyl-prolyl cis-trans isomerase (PPI, cyclophilins/FKBPs) (EC5.3.4.1)... 

Bachinger, H.P. (1987) The influence of peptidyl-prolyl cis-trans isomerase on the in vitro folding of type III collagens. Journal of Biobgical Chemistry 262, 17144-17148. 

Gothel, S.F. and Marahiel, M.A. (1999) Peptidyl-prolyl cis-trans isomerases, a superfamily of ubiquitous folding catalysts. Cellular and Molecular Life Sciences 55, 423-436. 

Schonbranner, E.R. and Schmid, F.X. (1992) Peptidyl-prolyl cis-trans isomerase improves the efficiency of protein disulfide isomerase as a catalyst of protein folding. Proceedings of the National Academy of Sciences USA 89, 4510-4513. 

A cytosolic binding protein for CsA was first isolated in 1984 and named cyclophilin, later cyclophilin A (CyPA), in reference to its high affinity for CsA (18). CyPA is a basic, abundant protein with a mass of 18 kDa, and it is found in a variety of tissues. The first clue to its function came in 1989 when two independent groups isolated the enzyme that catalyzes pepti-dyl proline isomerization/peptidylprolyl cis-trans isomerase (EC 5.2.1.8 PPIase), in protein chains and (re)discovered CyPA (19, 20). CyPA is a potent PPIase, and its enzymatic activity is strongly inhibited by CsA. 

Disulfide bond formation within the individual propeptides precedes folding and trimers are then formed by association of the C-terminal propeptides." Disulfide bonds between the chains are then formed and this formation is most likely catalyzed by PDI." As triple helix formation proceeds, the rate-limiting step in this process is the cis—trans isomerization of peptidyl-Pro bonds. This process can be catalyzed by peptidyl-prolyl cis—trans isomerases (cyclophilins and FKBPs). This activity is required to convert the proline residues to the trans form required for triple helix formation." " " ... 

In the protein s native conformation, every X-Pro bond has to have the correct conformation (cis or trans). As the uncatalyzed transition between the two forms is very slow, there is a proline cis-trans isomerase [2] in the ER that accelerates the conversion. 

This enzyme [EC 5.2.1.8] (also known as peptidylprolyl cis-trans isomerase, peptidylprolyl isomerase, and cyclophilin) catalyzes the interconversion of a peptidylprolyl derivative (in which co = 180°) and a peptidylprolyl derivative (in which co = 0°). 

ZEATIN CIS-TRANS ISOMERASE ZEATIN REDUCTASE ZEOLITE ZERO ORDER... 

What does tau do normally Although it has been studied for many years, its exact functions are elusive. However, the role of the microtubules in axonal transport is well established. The tau isoforms may play a functional role in this process. The hyperphosphorylated tau of Alzheimer disease doesn t promote proper assembly of microtubules and may interfere with axonal transport of materials along the microtubules (see p. 1119).1214 1215 Alzheimer disease may reflect an imbalance between the phosphorylation and dephosphorylation processes. Another possible problem with tau may be slow isomerization of prolyl linkages because of a deficiency of a prolyl cis-trans isomerase (Box 9-F).1216... 

Proteins spontaneously fold into their native conformation, with the primary structure of the protein dictating its three-dimensional structure. Protein folding is driven primarily by hydrophobic forces and proceeds through an ordered set of pathways. Accessory proteins, including protein disulfide isomerases, peptidyl prolyl cis-trans isomerases, and molecular chaperones, assist proteins to fold correctly in the cell. 

Galat, A. (1993). Peptidylproline cis-trans-isomerases Immunophilins. Eur. J. Biochem. 216, 689-707. 

Kay, J. E. (1996). Structure-function relationships in the FK506-binding protein (FKBP) family of peptidylprolyl cis-trans isomerases. Biochem.J. 314, 361-385. 

Peptidyl-propyl cis-trans isomerase Foldase Interconversion of peptidyl-propyl imide bonds cypB FKBP22... 

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