Long-chain unsaturated fatty acids, such as linoleic acid, show antibacterial activity and are the key ingredients of antimicrobial food additives and some antibacterial herbs. However, the precise mechanism for this antimicrobial activity remains unclear. We found that linoleic acid inhibited bacterial enoyl-acyl carrier protein reductase (FabI), an essential component of bacterial fatty acid synthesis, which has served as a promising target for antibacterial drugs. Additional unsaturated fatty acids including palmitoleic acid, oleic acid, linolenic acid, and arachidonic acid also exhibited the inhibition of FabI. However, neither the saturated form (stearic acid) nor the methyl ester of linoleic acid inhibited FabI. These FabI-inhibitory activities of various fatty acids and their derivatives very well correlated with the inhibition of fatty acid biosynthesis using [ 14 C] acetate incorporation assay, and importantly, also correlated with antibacterial activity. Furthermore, the supplementation with exogenous fatty acids reversed the antibacterial effect of linoleic acid, which showing that it target fatty acid synthesis. Our data demonstrate for the first time that the antibacterial action of unsaturated fatty acids is mediated by the inhibition of fatty acid synthesis.

The incidence and prevalence of CD and UC in Seoul, Korea, are still low compared with those in Western countries, but are rapidly increasing.

Factor VIII (fVIII) is a serum protein in the coagulation cascade that nucleates the assembly of a membrane-bound protease complex on the surface of activated platelets at the site of a vascular injury. Hemophilia A is caused by a variety of mutations in the factor VIII gene and typically requires replacement therapy with purified protein. We have determined the structure of a fully active, recombinant form of factor VIII (r-fVIII), which consists of a heterodimer of peptides, respectively containing the A1-A2 and A3-C1-C2 do IntroductionThe principal mechanism used to stop the loss of blood in mammals following vascular injury consists of a pair of overlapping proteolytic cascades called the extrinsic and intrinsic pathways. [1][2][3][4] The process of blood coagulation requires extraordinary spatial and temporal regulation, which is accomplished by assembling and tethering the central proteolytic activities of these cascades at the location of transiently exposed biomolecules and cellular surfaces ( Figure 1A). This includes an integral membrane protein called "tissue factor" that initiates the rapid up-regulation of the short-lived extrinsic pathway, 5 and the surfaces of activated platelets, which modulate the activation of the longer-lived intrinsic pathway. 6 A total of 2 homologous procoagulants, factors V and VIII (fV and fVIII), are each localized on the surface of these platelets, where they nucleate the assembly of multiprotein proteolytic complexes.When fVIII is bound to activated platelets at the site of vascular injury, it recruits the serine protease fIXa into a complex that then catalyzes the proteolytic activation of fX. 1,4,7 The proteolytic activity of fIXa is enhanced by approximately 200 000-fold through its interaction with fVIII, calcium, and the phospholipid bilayer, 8 corresponding to an increase of approximately 10 9 in k cat /K M .The full-length, unprocessed fVIII protein consists of 2332 amino acid residues and has the domain structure A1-A2-B-A3-C1-C2 9-12 ( Figure 1B). The 3 A domains are each approximately 330 residues, and approximately 40% identical to each other and to the copper-binding protein ceruloplasmin. 13 The C domains are smaller (approximately 160 residues) and are more distantly related to various members of the discoidin protein fold family, such as galactose oxidase. [14][15][16][17] The B domain has no known structural homologs, is heavily glycosylated, and is relatively dispensible for procoagulant activity. fVIII is initially processed by proteolytic cleavage events that remove a large portion of the B domain, generating a heterodimer that circulates in a tight complex with von Willebrand factor (VWF). 18 This interaction is essential for maintaining stable levels of fVIII in circulation. 19 Upon vascular injury, further proteolytic processing generates activated factor VIIIa (fVIIIa), a heterotrimer (A1/A2/A3-C1-C2) that is released from VWF and binds to activated platelets. 18 The carboxy-terminal 159 amino acids of fVIII comprise its C2 domain, which is invo...

The qFIT provides a higher sensitivity for detecting ACRN and cancer than the GT, and has an acceptable specificity that significantly reduces the need for colonoscopic evaluation in the screened population.

A 70-kDa protein was specifically induced in Escherichia coli when the culture temperature was shifted from 37 to 15°C. The protein was identified to be the product of the deaD gene (reassigned csdA) encoding a DEAD-box protein. Furthermore, after the shift from 37 to 15°C, CsdA was exclusively localized in the ribosomal fraction and became a major ribosomal-associated protein in cells grown at 15°C. The csdA deletion significantly impaired cell growth and the synthesis of a number of proteins, specifically the derepression of heat-shock proteins, at low temperature. Purified CsdA was found to unwind double-stranded RNA in the absence of ATP. Therefore, the requirement for CsdA in derepression of heat-shock protein synthesis is a cold shock-induced function possibly mediated by destabilization of secondary structures previously identified in the rpoH mRNA.Bacterial adaptation to various environmental stresses has been extensively investigated (reviewed in refs. 1-4). Interestingly, it has been demonstrated that Escherichia coli has an adaptive response not only to high temperature by inducing a group of heat-shock proteins but also to low temperature by inducing a group of cold-shock proteins (5, 6). In contrast to heat-shock proteins, which include protein chaperones required for protein folding and peptidases, cold-shock proteins appear to be involved in various cellular functions such as transcription, translation, and DNA recombination (5, 6).Among the cold-shock proteins of E. coli, CspA has been identified as the major cold-shock protein, which is almost exclusively produced at low temperature at a level of 250,000 molecules per cell (5, 7). The three-dimensional structure of CspA consisting of 69 amino acid residues has been determined, which is composed of five antiparallel (3-sheet structures (8,9). CspA binds to single-stranded DNA (8), and its possible function as an RNA chaperone has been speculated (6). In addition to CspA, E. coli contains a large family of CspA-like proteins consisting of CspB, CspC, CspD, and CspE, among which only CspB is a cold-shock protein (10, 11).In the present paper, we report a newly discovered coldshock protein of 70 kDa, which is also almost exclusively produced upon a temperature shift from 37 to 15°C, similar to the induction of CspA. It was found that this newly identified cold-shock protein is exclusively localized in the ribosomal fraction and became a major ribosomal-associated protein at low temperature. This protein was purified and identified to be the product of the gene that has been known as deaD. This gene had been isolated as a multicopy suppressor for a temperature-sensitive mutation located in the gene encoding ribosomal S2 protein and proposed to encode a putative ATP-dependent RNA helicase based on sequence similarities with other known DEAD-box proteins (12). This protein now is assigned CsdA for cold-shock DEAD-box protein A. We found that this protein has a helix-destabilizing activity. Disruption of the gene resulted in a defect in growth a...

Apoptosis signal-regulating kinase 1 (ASK1) is a mitogen-activated protein kinase kinase kinase that can activate the c-Jun N-terminal kinase and the p38 signaling pathways. It plays a critical role in cytokine-and stressinduced apoptosis. To further characterize the mechanism of the regulation of the ASK1 signal, we searched for ASK1-interacting proteins employing the yeast twohybrid method. The yeast two-hybrid assay indicated that mouse glutathione S-transferase Mu 1-1 (mGSTM1-1), an enzyme involved in the metabolism of drugs and xenobiotics, interacted with ASK1. We subsequently confirmed that mGSTM1-1 physically associated with ASK1 both in vivo and in vitro. The in vitro binding assay indicated that the C-terminal portion of mGSTM1-1 and the N-terminal region of ASK1 were crucial for binding one another. Furthermore, mGSTM1-1 suppressed stress-stimulated ASK1 activity in cultured cells. mG-STM1-1 also blocked ASK1 oligomerization. The ASK1 inhibition by mGSTM1-1 occurred independently of the glutathione-conjugating activity of mGSTM1-1. Moreover, mGSTM1-1 repressed ASK1-dependent apoptotic cell death. Taken together, our findings suggest that mGSTM1-1 functions as an endogenous inhibitor of ASK1. This highlights a novel function for mGSTM1-1 insofar as mGSTM1-1 may modulate stress-mediated signals by repressing ASK1, and this activity occurs independently of its well-known catalytic activity in intracellular glutathione metabolism.

Telomerase reverse transcriptase (TERT) is up-regulated in a variety of human neoplasms. Mutations in the core promoter region of the TERT gene, which increases promoter activity, have been reported in melanomas and a variety of human neoplasms, including gliomas. In the present study, we screened for TERT promoter mutations by direct DNA sequencing in a population-based collection of 358 glioblastomas. TERT promoter mutations (C228T, C250T) were detected in 55 % glioblastomas analysed. Of these, 73 % had a C228T mutation, and 27 % had a C250T mutation; only one glioblastoma had both C228T and C250T mutations. TERT promoter mutations were significantly more frequent in primary (IDH1 wild-type) glioblastomas (187/322; 58 %) than in secondary (IDH1 mutated) glioblastomas (10/36, 28 %; P = 0.0056). They showed significant inverse correlations with IDH1 mutations (P = 0.0056) and TP53 mutations (P = 0.043), and a significant positive correlation with EGFR amplification (P = 0.048). Glioblastoma patients with TERT mutations showed a shorter survival than those without TERT mutations in univariate analysis (median, 9.3 vs. 10.5 months; P = 0.015) and multivariate analysis after adjusting for age and gender (HR 1.38, 95 % CI 1.01-1.88, P = 0.041). However, TERT mutations had no significant impact on patients' survival in multivariate analysis after further adjusting for other genetic alterations, or when primary and secondary glioblastomas were separately analysed. These results suggest that the prognostic value of TERT mutations for poor survival is largely due to their inverse correlation with IDH1 mutations, which are a significant prognostic marker of better survival in patients with secondary glioblastomas.

Rectal sensitivity was enhanced in D-IBS patients with moderately increased mucosal mast cells, but it was attenuated in patients with markedly increased ones. This study might provide evidence for an important role of mast cells in visceral hypersensitivity.