The outer membrane protein A (OmpA) plays important roles in anchoring of the to bacterial cell wall. C-terminal periplasmic domain OmpA (OmpA-like domain) associates with peptidoglycan (PGN) layer noncovalently. However, there is a paucity information on structural aspects mechanism PGN recognition by OmpA-like domains. To elucidate this molecular process, we solved high-resolution crystal structure an from Acinetobacter baumannii bound diaminopimelate (DAP), unique amino acid PGN. clearly...

IsdG and IsdI are paralogous proteins that intracellular components of a complex heme uptake system in Staphylococcus aureus. were shown previously to reductively degrade hemin. Crystal structures the apoproteins show these belong newly identified degradation family distinct from canonical eukaryotic prokaryotic oxygenases. Here we report crystal an inactive N7A variant with Fe(3+)-protoporphyrin IX (IsdG-hemin) cobalt protoporphyrin (IsdI-CoPPIX) 1.8 A or better resolution. These...

The crystal structure of a major oxygen-insensitive nitroreductase (NfsA) from <i>Escherichia coli</i> has been solved by the molecular replacement method at 1.7-Å resolution. This enzyme is homodimeric flavoprotein with one FMN cofactor per monomer and catalyzes reduction nitrocompounds using NADPH. exhibits an α + β-fold, comprised central domain excursion domain. overall NfsA similar to NADPH-dependent flavin reductase of<i>Vibrio harveyi</i>, despite definite difference in spatial...

Despite recent progress in research on the Hippo signalling pathway, structural information available this area is extremely limited. Intriguingly, homodimeric and heterodimeric interactions of mammalian sterile 20-like (MST) kinases through so-called `SARAH' (SAV/RASSF/HPO) domains play a critical role cellular homeostasis, dictating fate cell regarding proliferation or apoptosis. To understand mechanism heterodimerization SARAH domains, three-dimensional structures an MST1–RASSF5...

Hosts utilize macroautophagy/autophagy to clear invading bacteria; however, bacteria have also developed a specific mechanism survive by manipulating the host cell autophagy mechanism. One pathogen, Legionella pneumophila, can hinder using effector protein RavZ that cleaves phosphatidylethanolamine-conjugated LC3 on phagophore membrane. However, detailed molecular mechanisms associated with function of hitherto remained unclear. Here, we report biochemical characteristics RavZ-LC3...

Recent progress in the development of peptide-derived Polo-like kinase (Plk1) polo-box domain (PBD) inhibitors has led to synthesis multiple peptide ligands with high binding affinity and selectivity. However, few systematic analyses have been conducted identify key Plk1 residues characterize their interactions potent inhibitors. We performed deletion analysis using most 4j studied N-terminal capping minimal diverse organic moieties, leading identification peptidomimetic 8 (AB-103) series To...

The Syd protein has been implicated in the Sec-dependent transport of polypeptides across bacterial inner membrane. Using Nanodiscs, we here provide direct evidence that binds SecY complex, and demonstrate interaction involves two electropositive cytosolic loops subunit. We solve crystal structure together with cysteine cross-link analysis, show a conserved concave electronegative groove constitutes SecY-binding site. At membrane, decreases activity translocon containing loosely associated...

The release of SO 2 from petroleum products derived crude oil, which contains sulfur compounds such as dibenzothiophene ( DBT ), leads to air pollution. ‘4S’ metabolic pathway catalyzes the sequential conversion 2‐hydroxybiphenyl via three enzymes encoded by dsz operon in several bacterial species. DszC monooxygenase), Rhodococcus erythropolis D‐1 is involved first two steps pathway. Here, we determined crystal structure FMN ‐bound DszC, and found that distinct conformations occur loop...

GTP and branched-chain amino acids (BCAAs) are metabolic sensors that indispensable for the determination of status cells. However, their molecular sensing mechanism remains unclear. CodY is a unique global transcription regulator recognizes BCAAs as specific signals affects expression more than 100 genes associated with metabolism. Herein, we report first crystal structures full-length complex molecules describe functional states. We observed two different oligomeric states CodY: dimeric...

The desulfurization of dibenzothiophene in Rhodococcus erythropolis is catalyzed by two monooxygenases, DszA and DszC, a desulfinase, DszB. In the last step this pathway, DszB hydrolyzes 2'-hydroxybiphenyl-2-sulfinic acid into 2-hydroxybiphenyl sulfite. We report on crystal structures an inactive mutant complex with substrates at resolutions 1.8A or better. overall fold similar to those periplasmic substrate-binding proteins. substrate complexes, biphenyl rings are recognized extensive...

Brazzein is the smallest sweet-tasting protein and was isolated from wild African plant Pentadiplandra brazzeana. The brazzein molecule consists of 54 amino-acid residues four disulfide bonds. Here, first crystal structure reported at 1.8 Å resolution compared with previously solution structures. Despite overall structural similarity, there are several remarkable differences between structures both in their backbone folds side-chain conformations. Firstly, an additional α-­helix structure....

4-Hydroxyphenylacetate (4-HPA) is oxidized as an energy source by two component enzymes, the large (HpaB) and small (HpaC). HpaB a 4-HPA monooxygenase that utilizes FADH2 supplied flavin reductase HpaC. We determined crystal structure of HpaC (ST0723) from aerobic thermoacidophilic crenarchaeon Sulfolobus tokodaii strain 7 in its three states [NAD(P)+-free, NAD+-bound, NADP+-bound]. exists homodimer, each monomer was found to contain FMN. preferred FMN FAD because there not enough space...

In the microbial dibenzothiophene desulfurization pathway, 2′-hydroxybiphenyl-2-sulfinate is converted to 2-hydroxybiphenyl and sulfinate by desulfinase (DszB) at last step, this reaction rate-limiting for whole pathway. The catalytic activity thermostability of DszB were enhanced two amino acid substitutions. Based on information 3-D structure a comparison sequences between reported thermophilic thermostable homologs (TdsB BdsB), residues, Tyr63 Gln65, selected as targets mutate improve...

Abstract Saccharomyces cerevisiae Est1p is a telomerase‐associated protein essential for telomere length homeostasis. hEST1A one of the three human homologues and considered to be involved not only in regulation elongation or capping but also nonsense‐mediated degradation RNA. composed two conserved regions, homology PIN ( Pi lT N ‐terminus) domains. The present study shows crystal structure domain at 1.8 Å resolution. overall an α/β fold core similar counterpart 5′ nucleases extended absent...

Cavitein Q4 is a template assembled synthetic protein designed for X-ray crystallographic analysis. It based on previous monomeric helical bundle cavitein (N1GG) that consists of four identical parallel peptides. Crystals were grown in the presence bromide ions used to solve initial phases via single-wavelength anomalous dispersion (SAD). A 1.4 Å resolution data set was then refined starting with SAD provide crystal structure Q4. The revealed as an asymmetric dimer, although appears be...

ABSTRACT The dibenzothiophene (DBT) sulfone monooxygenase BdsA from Bacillus subtilis WU‐S2B catalyzes the conversion of DBT to 2′‐hydroxybiphenyl 2‐sulfinate. We report crystal structures at a resolution 2.80 Å. exists as homotetramer with dimer‐of‐dimers configuration in crystal, and interaction between E288 R296 is important for tetramer formation. A structural comparison homologous proteins shows that orientation location α9‐α12 helices are closer those closed form than open EDTA EmoA....

Over the years, a great deal of effort has been focused on design and synthesis potent, linear peptide inhibitors targeting polo-like kinase 1 (Plk1), which is critically involved in multiple mitotic processes established as an adverse prognostic marker for tumor patients. Plk1 localizes to its intracellular anchoring sites via polo-box domain, inhibiting domain considered approach circumvent specificity problems associated with conserved adenosine triphosphate-binding pocket. The consists...

Thermotoga maritima, a deep-branching hyperthermophilic bacterium, expresses an extraordinarily stable maritima acyl carrier protein (Tm-ACP) that functions as in the fatty acid synthesis system at near-boiling aqueous environments. Here, to understand hyperthermal adaptation of Tm-ACP, we investigated structure and dynamics Tm-ACP by nuclear magnetic resonance (NMR) spectroscopy. The melting temperature (101.4 °C) far exceeds other ACPs, owing extensive ionic interactions tight hydrophobic...

Abstract Aryl polyenes (APE) are one of the most widespread secondary metabolites among gram-negative bacteria. In Acinetobacter baumannii , strains belonging to virulent global clone 2 (GC2) mostly contain APE biosynthesis genes; its relevance in elevated pathogenicity is great interest. gene clusters harbor two ketosynthases (KSs): heterodimeric KS-chain length factor complex, ApeO-ApeC, and homodimeric ketoacyl-acyl carrier protein synthase I (FabB)-like KS, ApeR. The role KSs unclear. We...

The YjgF/YER057c/UK114 family of proteins (referred to as the YjgF in this article) includes over 200 prokaryotic and eukaryotic consisting ca. 130 amino acid residues.1 protein members show diverse functions. In bacteria yeasts, they play prerequisite roles biosynthesis essential compounds such isoleucine,2-4 thiamine,2 purine.5 For example, gene disruption a yeast member that is involved isoleucine lethal cells.4 On other hand, mammalian members, whose expression upregulated upon cellular...