Abstract Organotin compounds such as triphenyltin (TPT) and tributyltin (TBT) act endocrine disruptors through the peroxisome proliferator–activated receptor γ (PPARγ) signaling pathway. We recently found that TPT is a particularly strong agonist of PPARγ. To elucidate mechanism underlying organotin-dependent PPARγ activation, we here analyzed interactions ligand-binding domain (LBD) with TBT by using X-ray crystallography mass spectroscopy in conjunction cell-based activity assays. Crystal...

X-ray analysis has been carried out on a crystal of the collagen model peptide (Hyp(R)-Hyp(R)-Gly)10 [where Hyp(R) is 4(R)-hydroxyproline] with 1.5 A resolution. The triple-helical structure same helical parameters and Rich Crick II hydrogen bond patterns as those other peptides. However, our full-length revealed that almost all consecutive residues take up-up pucker in contrast to putative down-up puckering propensities unique feature thermodynamic associated conformational transition this...

Dynamic remodeling of the extracellular matrix affects many cellular processes, either directly or indirectly, through regulation soluble ligands; however, mechanistic details this process remain largely unknown. Here we propose that type I collagen regulates receptor-binding activity pigment epithelium-derived factor (PEDF), a widely expressed secreted glycoprotein has multiple important biological functions in tissue and organ homeostasis. We determined crystal structure PEDF complex with...

BEC-producing Clostridium perfringens is a causative agent of foodborne gastroenteritis. It was first reported in 2014, and since then, several isolates have been identified Japan the United Kingdom. The novel binary ADP-ribosylating toxin BEC, which consists two components (BECa BECb), encoded on plasmid that similar to pCP13 harbours conjugation locus, called Pcp, encoding homologous proteins type 4 secretion system. Despite high vitro frequency pCP13, its dissemination related plasmids,...

Extensive studies on the structure of collagen have revealed that hydroxylation Pro residues in a variety model peptides with typical (X-Y-Gly)(n) repeats (X and Y: its analogues) represents one major factors influencing stability triple helices. While(2S,4R)-hydroxyproline (Hyp) at position Y stabilizes helix, (2S,4S)-hydroxyproline (hyp) X-position destabilizes helix as demonstrated (hyp-Pro-Gly)(15) is less stable than (Pro-Pro-Gly)(15) shorter peptide (hyp-Pro-Gly)(10) does not form...

Significance To avoid the mucosal barrier and attach to intestinal epithelium, enteric pathogens have evolved a unique proteinaceous fiber called type IVb pilus (T4bP). Despite its importance for bacterial pathogenesis, little is known about adhesion mechanisms of T4bP, especially regarding role minor pilin subunit located at tip. Here, we show that CofB CFA/III from enterotoxigenic Escherichia coli (ETEC) plays not only in T4bP assembly by forming trimeric initiator complex, but also...

In order to elucidate the relationship between stability and structure of monohaem cytochrome c555 (AA c555) from hyperthermophilic bacterium Aquifex aeolicus, chemical denaturation crystal determination were carried out. AA exhibited higher than thermophilic Hydrogenobacter thermophilus c552 (HT c552), which is one most stable cytochromes c. The three-dimensional c555, was determined using multiple anomalous dispersion technique at 1.15 Å resolution, included a unique 14-residue extra...

Thermophilic Hydrogenophilus thermoluteolus cytochrome c' (PHCP) exhibits higher thermal stability than a mesophilic counterpart, Allochromatium vinosum (AVCP), which has homo-dimeric structure and ligand-binding ability. To understand the mechanism ability of thermally stable PHCP protein, crystal was first determined. It formed structure, main chain root mean square deviation (rmsd) value between AVCP being 0.65 Å. In six specific residues appeared to strengthen heme-related...

A new piezoelectric sensor was developed in the shape of a traditional Japanese braided cord known as Kumihimo by weaving poly-l-lactic acid (PLLA) fibers (piezoelectric PLLA cord). We found that tied various decorative knots, and worn an accessory such choker or necklace, can detect pulse waves, swallowing, coughing systematic way one's daily life. To demonstrate this, we system for measuring waves with Wi-Fi communication using knots.

Adiponectin, an anti-atherogenic and insulin-sensitizing adipokine, forms multiple isoforms including a trimer, hexamer heavier oligomers (mainly octadecamer) that determine their biological activities. We designed 89-residue peptides containing modifications found in the collagenous domain of native adiponectin. Circular dichroism analytical ultracentrifugation measurements showed peptide bearing glucosyl-galactosyl-hydroxylysine residues stable collagen-like triple helical structure...

Many bioactive proteins interact with collagen, recognizing amino acid sequences displayed on the triple helix. We report here a selection strategy to obtain triple-helical peptides that from combinatorial random library constructed in yeast cells. This system enables us select them using standard two-hybrid protocol, detecting interactions between and target fused GAL4-activating binding domains, respectively. The was having "host-guest" design which host helix-stabilizing regions flanked...

CofA, a major pilin subunit of colonization factor antigen III (CFA/III), forms pili that mediate small-intestinal by enterotoxigenic Escherichia coli (ETEC). In this study, the crystal structure an N-terminally truncated version CofA was determined single-wavelength anomalous diffraction (SAD) phasing using five sulfurs in protein. Given counterbalance between signal strength and undesired X-ray absorption solvent, data were collected at 1.5 Å resolution synchrotron radiation. These...

We present a mass spectrometric method for analyzing protein structure and function, based on the imidazole C-2 or histidine Cε1 hydrogen/deuterium (H/D) exchange reaction, which is intrinsically second-order with respect to concentrations of imidazolium cation OD– in D2O. The rate constant (k2) this reaction was calculated from pH dependency pseudo-first-order (kφ) obtained change average [ΔMr (0 ≤ ΔMr < 1)] peptide fragment containing defined residue at incubation time (t) such that kφ =...

Monomeric cytochrome c5 from deep-sea piezophilic Shewanella violacea (SVcytc5) was stable against heat and denaturant compared with the homologous protein shallow-sea piezo-sensitive livingstonensis (SLcytc5). Here, SVcytc5 crystal structure revealed that Lys-50 side chain on flexible loop formed a hydrogen bond heme whereas of corresponding hydrophobic Leu-50 could not form such in SLcytc5, which appeared to be one possible factors responsible for difference stability between two proteins....

Cytochrome c ′-β is a heme protein that belongs to the cytochrome P460 family and consists of homodimeric subunits with predominantly antiparallel β-sheet fold. Here, crystal structure from thermophilic Thermus thermophilus (TTCP-β) reported at 1.74 Å resolution. TTCP-β has typical fold similar moderately Methylococcus capsulatus (MCCP-β). The phenylalanine cap around distal side also in MCCP-β, indicating both proteins similarly bind nitric oxide carbon monoxide, as observed...

Abstract A 12‐residue MST isolated from a marine organism is potent serine protease inhibitor that has double cyclic structure composed of two ester linkages formed between the β‐hydroxyl and β‐carboxyl groups, Thr 3 ‐Asp 9 Ser 8 11 . was synthesized by regioselective esterification procedure employing sets orthogonally removable side‐chain protecting groups for Asp Ser/Thr residues. In molecule, there were no significant changes observed in yield changing order esterification. SAR study...

We have characterized various structures of (Pro-Hyp(R)-Gly)(3)-Pro-fPro(R)-Gly-(Pro-Hyp(R)-Gly)(3) in the process cis-trans isomerization and helix-coil transition by exploiting sole (19)F NMR probe 4(R)-fluoroproline (fPro(R)). Around temperature (T(m)), we detected a species with triple helical structure distinct from ordinary one concerning alignment three strands. The (19)F-(19)F exchange spectroscopy showed that this misaligned helices were interchangeable only indirectly via an...

Binary enterotoxin of Clostridium perfringens (BEC), consisting the components BECa and BECb, was recently identified as a novel produced by C. that causes acute gastroenteritis in humans. Although detailed mechanism cell intoxication BEC remains to be defined, shows both NAD+-glycohydrolase actin ADP-ribosyltransferase activities presence NAD+. In this study, we determined first crystal structure its apo-state complex with NADH. The striking resemblance other binary ADP-ribosylating toxins...

Colonization of the host intestine is most important step in Vibrio cholerae infection. The toxin-coregulated pilus (TCP), an operon-encoded type IVb (T4bP), plays a crucial role this process, which requires additional secreted protein, TcpF, encoded on same TCP operon; however, its mechanisms secretion and function remain elusive. Here, we demonstrated that TcpF interacts with minor pilin, TcpB, elucidated crystal structures TcpB alone complex TcpF. structural analyses reveal how recognizes...

Conformational preferences of the (2S,4R)-4-chloroproline (Clp) and (2S,4S)-4-chloroproline (clp) residues are explored at M06-2X/cc-pVTZ//M06-2X/6-31+G(d) level theory in gas phase water, where solvation free energies were calculated using implicit model, by an X-ray diffraction study solid state. In phase, down-puckered γ-turn structure with trans prolyl peptide bond is most preferred for both Ac-Clp-NHMe Ac-clp-NHMe, which C(7) hydrogen between two terminal groups seems to play a role, as...