The prolyl isomerase cyclophilin A (CypA) is required for efficient HIV-1 replication and is incorporated into virions through a binding interaction at the Gly-Pro(222) bond located within the capsid domain of the HIV-1 Gag precursor polyprotein (Pr(gag)). It has recently been shown that CypA efficiently catalyzes the cis/trans isomerization of Gly-Pro(222) within the isolated N-terminal domain...

The peptide toxins of poisonous Amanita mushrooms are bicyclic octapeptides (amatoxins) or heptapeptides (phallotoxins). In Amanita bisporigera, alpha-amanitin and phallacidin are synthesized as 35- and 34-amino acid proproteins, respectively, in which the amino acid sequences found in the mature toxins are flanked by conserved amino acid sequences. The presence of invariant Pro residues immedi...

1. Mair J, Hammerer-Lercher A, Puschendorf B. The impact of cardiac natriuretic peptide determination on the diagnosis and management of heart failure [Review]. Clin Chem Lab Med 2001;39:571–88. 2. Mir TS, Laux R, Hellwege HH, Liedke B, Heinze C, von Buelow H, et al. Plasma concentrations of aminoterminal pro atrial natriuretic peptide and aminoterminal pro brain natriuretic peptide in healthy ...

The product ion spectra of proline-containing peptides are commonly dominated by yn ions generated by cleavage at the N-terminal side of proline residues. This proline effect is investigated in the current work by collision-induced dissociation (CID) of protonated Ala-AlaXxx-Pro-Ala (Xxx includes Ala, Ser, Leu, Val, Phe, and Trp) in an electrospray/quadrupole/timeof-flight (QqTOF) mass spectrom...

Molecular dynamics simulations of alpha-lytic protease (alphaLP) alone and complexed with its pro region (PRO) are performed to understand the origin of its high unfolding (and folding) barrier when it is alone and how the pro region lowers this barrier. At room temperature, alphaLP exhibits lower dynamic fluctuations than alpha-chymotrypsin. Simulation of PRO alone led to reorientation of its ...

Vibrio cholerae produces a cytolytic toxin named El Tor cytolysin/hemolysin which is encoded by the hlyA gene. This cytolysin is produced as a 79-kDa precursor form (pro-HlyA) into the culture supernatant after cleavage of the signal peptide of the hlyA product (prepro-HlyA). The pro-HlyA is then processed to a 65-kDa mature cytolysin (mature HlyA) after cleavage of the 15-kDa N-terminal peptid...

The extracellular bacterial protease, alpha-lytic protease (alphaLP), is synthesized with a large, two-domain pro region (Pro) that catalyzes the folding of the protease to its native conformation. In the absence of its Pro folding catalyst, alphaLP encounters a very large folding barrier (DeltaG = 30 kcal mol(-1)) that effectively prevents the protease from folding (t(1/2) of folding = 1800 ye...

The precursor protein of von Willebrand factor (pro-vWF) consists of four different repeated domains, denoted D1-D2-D'-D3-A1-A2-A3-D4-B1-B2-B3-C1-C2, followed by a carboxy-terminal region of 151 amino acids without obvious internal homology. Previously, we have shown the requirement of the domains D1, D2, D', and D3 of pro-vWF in the assembly of pro-vWF dimers into multimers. Here, we define th...

We investigated the proteolytic processing of mouse pro-GHRH [84 amino acids (aa)] by furin, PC1/3, PC2, and PC5/6A. We created six point mutations in the N- and C-terminal cleavage sites, RXXR decreased and RXRXXR decreased, respectively. The following results were obtained after transient transfection/cotransfection and metabolic pulse-chase labeling studies in several neuroendocrine cells. 1...