In bacterial chemotaxis, chemoreceptors in signaling complexes modulate the activity of two-component histidine kinase CheA in response to chemical stimuli. CheA catalyzes phosphoryl transfer from ATP to a histidinyl residue of its P1 domain. That phosphoryl group is transferred to two response regulators.
View Article and Find Full Text PDFEthylenediaminetetraacetate (EDTA) is the most abundant organic pollutant in surface water because of its extensive usage and the recalcitrance of stable metal-EDTA complexes. A few bacteria including Chelativorans sp. BNC1 can degrade EDTA with a monooxygenase to ethylenediaminediacetate (EDDA) and then use iminodiacetate oxidase (IdaA) to further degrade EDDA into ethylenediamine in a two-step oxidation.
View Article and Find Full Text PDFPhenylalanine ammonia-lyase (PAL) is the first enzyme of the general phenylpropanoid pathway catalyzing the nonoxidative elimination of ammonia from l-phenylalanine to give -cinnamate. In monocots, PAL also displays tyrosine ammonia lyase (TAL) activity, leading to the formation of -coumaric acid. The catalytic mechanism and substrate specificity of a major PAL from sorghum (; SbPAL1), a strategic plant for bioenergy production, were deduced from crystal structures, molecular docking, site-directed mutagenesis, and kinetic and thermodynamic analyses.
View Article and Find Full Text PDFCinnamyl alcohol dehydrogenase (CAD) catalyzes the final step in monolignol biosynthesis, reducing sinapaldehyde, coniferaldehyde, and -coumaraldehyde to their corresponding alcohols in an NADPH-dependent manner. Because of its terminal location in monolignol biosynthesis, the variation in substrate specificity and activity of CAD can result in significant changes in overall composition and amount of lignin. Our in-depth characterization of two major CAD isoforms, SbCAD2 (Brown midrib 6 [bmr6]) and SbCAD4, in lignifying tissues of sorghum (), a strategic plant for generating renewable chemicals and fuels, indicates their similarity in both structure and activity to Arabidopsis () CAD5 and sinapyl alcohol dehydrogenase, respectively.
View Article and Find Full Text PDFEthylenediaminetetraacetate (EDTA) is currently the most abundant organic pollutant due to its recalcitrance and extensive use. Only a few bacteria can degrade it, using EDTA monooxygenase (EmoA) to initiate the degradation. EmoA is an FMNH2 -dependent monooxygenase that requires an NADH:FMN oxidoreductase (EmoB) to provide FMNH2 as a cosubstrate.
View Article and Find Full Text PDFIncreased survival of cancer cells mediated by high levels of ionizing radiation (IR) reduces the effectiveness of radiation therapy for non-small cell lung cancer (NSCLC). In the present study, danshensu which is a selected component of traditional oriental medicine (TOM) compound was found to reduce the radioresistance of NSCLC by inhibiting the nuclear factor-κB (NF-κB) pathway. Of the various TOM compounds reported to inhibit the IR activation of NF-κB, danshensu was chosen as a final candidate based on the results of structural comparisons with human metabolites and monoamine oxidase B (MAOB) was identified as the putative target enzyme.
View Article and Find Full Text PDFFrequent relapse and spreading of tumors during radiotherapy are principal obstacles to treatment of non-small cell lung cancer (NSCLC). In this study, we aimed to investigate how macrophage migration inhibitory factor (MIF) which is expressed at high levels in metastatic and primary lung cancer cells could regulate NSCLC metastasis in response to ionizing radiation (IR). The results indicated that MIF and ribosomal protein S3 (rpS3) were shown to be connected to inflammation, proliferation, and metastasis of NSCLC via IR-induced activation of the NF-κB pathway.
View Article and Find Full Text PDFWe examined that the protective effects of ANX1 on 12-O-tetradecanoylphorbol- 13-acetate (TPA)-induced skin inflammation in animal models using a Tat-ANX1 protein. Topical application of the Tat-ANX1 protein markedly inhibited TPAinduced ear edema and expression levels of cyclooxygenase-2 (COX-2) as well as pro-inflammatory cytokines such as interleukin- 1 beta (IL-1 β), IL-6, and tumor necrosis factor-alpha (TNF-α). Also, application of Tat-ANX1 protein significantly inhibited nuclear translocation of nuclear factor-kappa B (NF-κ B) and phosphorylation of p38 and extracellular signalregulated kinase (ERK) mitogen-activated protein kinase (MAPK) in TPA-treated mice ears.
View Article and Find Full Text PDFEDTA has become a major organic pollutant in the environment because of its extreme usage and resistance to biodegradation. Recently, two critical enzymes, EDTA monooxygenase (EmoA) and NADH:FMN oxidoreductase (EmoB), belonging to the newly established two-component flavin-diffusible monooxygenase family, were identified in the EDTA degradation pathway in Mesorhizobium sp. BNC1.
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