Parvulin

Parvulin

Parvulin, a 92-amino acid protein discovered in E. coli in 1994,Rahfeld JU, Schierhorn A, Mann KH. (1994). A novel peptidyl-prolyl cis/trans isomerase from Escherichia coli. "FEBS Lett" 343:65.] is the smallest known protein with prolyl isomerase activity, which catalyzes the "cis"-"trans" isomerization of proline peptide bonds. Although parvulin has no homology with larger prolyl isomerases such as cyclophilin and FKBP, it does share structural features with subdomains of other proteins involved in preparing secreted proteins for export from the cell. Balbach J, Schmid FX. (2000). Proline isomerizarion and its catalysis in protein folding. "In Mechanisms of Protein Folding" 2nd ed. Ed. RH Pain. "Frontiers in Molecular Biology" series. Oxford University Press: Oxford, UK.]

Although parvulin is as active as the larger prolyl isomerases against a short proline-containing test peptide, it has lower relative activity against biological substrates, possibly because the larger molecules have a higher ability to bind the substrate peptide.Scholz C, Rahfeld J, Fischer G, Schmid FX. (1997). Catalysis of protein folding by parvulin. "J Mol Biol" 273(3):752-62.] Parvulin itself contains proline residues and its folding can be accelerated by the presence of cyclophilin; parvulin folding can also be autocatalytic.

A eukaryotic homolog of parvulin known as Pin1 is required to execute the transition from G2 phase to M phase in the cell cycle.Gothel SF, Marahiel MA. (1999). Peptidyl-prolyl cis-trans isomerases, a superfamily of ubiquitous folding catalysts. "Cell Mol Life Sci" 55(3):423-36.] Absence of Pin1 activity in humans has also been implicated in the folding and processing of the amyloid precursor protein, whose degradation product is the cytotoxic peptide amyloid beta implicated in Alzheimer's disease.Pastorino L, Sun A, Lu PJ, Zhou XZ, Balastik M, Finn G, Wulf G, Lim J, Li SH, Li X, Xia W, Nicholson LK, Lu KP. (2006). The prolyl isomerase Pin1 regulates amyloid precursor protein processing and amyloid-beta production. "Nature" 440(7083):528-34. ]

References


Wikimedia Foundation. 2010.

Игры ⚽ Поможем сделать НИР

Look at other dictionaries:

  • PIN4 — Protein (peptidylprolyl cis/trans isomerase) NIMA interacting, 4 (parvulin), also known as PIN4, is a human gene.cite web | title = Entrez Gene: PIN4 protein (peptidylprolyl cis/trans isomerase) NIMA interacting, 4 (parvulin)| url =… …   Wikipedia

  • Prolyl isomerase — (also PPIase) is an enzyme found in both prokaryotes and eukaryotes that interconverts the cis and trans isomers of peptide bonds with the amino acid proline. Proline has an unusually conformationally restrained peptide bond due to its cyclic… …   Wikipedia

  • Cyclophilin — peptidylprolyl isomerase A (cyclophilin A) Ribbon diagram of cyclophilin A in complex with ciclosporin (yellow). From PDB 1CWA …   Wikipedia

  • Biochemistry of Alzheimer's disease — The biochemistry of Alzheimer s disease (AD), one of the most common causes of adult dementia, is as yet not well understood at the molecular level. It has been identified as a protein misfolding disease due to the accumulation of abnormally… …   Wikipedia

  • Fibrillarin — Fibrillarin, also known as FBL, is a human gene.cite web | title = Entrez Gene: FBL fibrillarin| url = http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene Cmd=ShowDetailView TermToSearch=2091| accessdate = ] PBB Summary section title = summary text …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”