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21.
Xinyue Ye Jian Wang Pengfei Xu Xiaoqian Yang Qixue Shi Genyan Liu Zhaoshi Bai Changlin Zhou Lingman Ma 《Microbial biotechnology》2023,16(9):1755-1773
Polymyxin resistance is conferred by MCR-1 (mobile colistin resistance 1)-induced lipopolysaccharide (LPS) modification of G− bacteria. However, the peptide MSI-1 exerts potent antimicrobial activity against mcr-1-carrying bacteria. To further investigate the potential role of MCR-1 in improving bacterial virulence and facilitating immune evasion, and the immunomodulatory effect of peptide MSI-1, we first explored outer membrane vesicle (OMV) alterations of mcr-1-carrying bacteria in the presence and absence of sub-MIC MSI-1, and host immune activation during bacterial infection and OMV stimulation. Our results demonstrated that LPS remodelling induced by MCR-1 negatively affected OMV formation and protein cargo by E. coli. In addition, MCR-1 diminished LPS-stimulated pyroptosis but facilitated mitochondrial dysfunction, further aggravating apoptosis in macrophages induced by OMVs of E. coli. Similarly, TLR4-mediated NF-κB activation was markedly alleviated once LPS was modified by MCR-1. However, peptide MSI-1 at the sub-MIC level inhibited the expression of MCR-1, further partly rescuing OMV alteration and attenuation of immune responses in the presence of MCR-1 during both infection and OMV stimulation, which can be exploited for anti-infective therapy. 相似文献
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Self incompatibility (SI) in Phalaris coerulescens is gametophytically determined by two unlinked multi allelic loci (S and Z). Neither the S nor Z genes have yet been cloned. As part of a map-based cloning strategy, high-resolution maps of the S and Z regions were generated from distorted segregating populations using RFLP probes from wheat, barley, oat, and Phalaris. The S locus was delimited to 0.26 cM with two boundary markers (Xwg811 and Xpsr168) and cosegregated with Xbm2 and Xbcd762. Xbcd266 was the closest marker linked to Z (0.9 cM). A high level of colinearity in the S and Z regions was found in both self-incompatible and -compatible species. The S locus was localized to the subcentromere region of chromosome 1 and the Z locus to the long arm end of chromosome 2. Several rice BAC clones orthologous to the S and Z locus regions were identified. This opens the possibility of using the rice genome sequence data to generate more closely linked markers and identify SI candidate genes. These results add further support to the conservation of gene order in the S and Z regions of the grass genomes. 相似文献
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A reinvestigation of the alphatic nitro-compounds in Astragalus canadensis resulted in the identification of two new esters of glucose with 3-nitropropanoic acid and 5-oxotetrahydrofuran-3-acetic acid, together with six known conjugates of 3-nitropropanoic acid. 1H and 13CNMR data are reported for the new compounds. 相似文献
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S. W. Englander L. Mayne Y. Bai T. R. Sosnick 《Protein science : a publication of the Protein Society》1997,6(5):1101-1109
This discussion, prepared for the Protein Society's symposium honoring the 100th anniversary of Kaj Linderstrøm-Lang, shows how hydrogen exchange approaches initially conceived and implemented by Lang and his colleagues some 50 years ago are contributing to current progress in structural biology. Examples are chosen from the active protein folding field. Hydrogen exchange methods now make it possible to define the structure of protein folding intermediates in various contexts: as tenuous molten globule forms at equilibrium under destabilizing conditions, in kinetic intermediates that exist for less than one second, and as infinitesimally populated excited state forms under native conditions. More generally, similar methods now find broad application in studies of protein structure, energetics, and interactions. This article considers the rise of these capabilities from their inception at the Carlsberg Labs to their contemporary role as a significant tool of modern structural biology. 相似文献
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To understand the genetic regulation of vegetative to reproductive transition in higher plants, further characterization of the Arabidopsis mutant embryonic flower1, emf1, was conducted. Using three flowering symptoms, we showed that emf1 mutants could only grow reproductive and not rosette shoots under five different growth conditions. The mutant embryos did not produce the typical tunica–corpus shoot apical structures at the heart-, torpedo-, and mature stages. The divergent shoot apical development during mutant and wild-type embryogenesis indicated that the wild-type EMF1 gene was expressed in early embryogenesis. Mutations in the EMF1 gene affected the embryonic shoot apical development and caused the germinating embryo and regenerating callus to grow inflorescence, instead of rosette, shoots. Our results support the hypothesis that the EMF1 gene regulates the switch between vegetative and reproductive growth in Arabidopsis. 相似文献
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The species of flies breeding in bovine manure, their parasites and predators as well as other associated arthropods in 3
localities in and near Bangalore are recoreded. The flies areMusca domestica L.,Musca pattoni
Austen,Stomoxys calcitrans L.,Physiphora aenea F.,Physiphora demandata F.,Sargus metallinus F.,Sepsis thoracica R.-D.,Sepsis nitens
Wiedemann,Sphaerocera scabricula
Hal, andLeptocera (Coproica) hirtula
Rondani. Four species of hymenopterous pupal parasites of these flies have been obtained:Spalangia cameroni
Perkins from pupae ofM. domestica, M. pattoni, S. calcitrans, P. aenea andP. demandata; Spalangia endius
Walker from pupae ofM. domestica, M. pattoni andS. calcitrans; Spalangia nigroaenea
Curtis from pupae ofM. domestica andS. calcitrans; andDirhinus trichiophthalmus
Masi from pupae ofSargus metallinus F. Percentage parasitism of fly puparia in field samples was noted. Four species ofHister andAleochara puberula
Klug feeding on various immature stages ofM. domestica, 2 species of scarabaeid beetles, 2 species of ants and a pseudoscorpion were also found in the manure. The importance of
biotic regulatory factors in the control of flies is discussed.
Paper presented at the seminar on utilization of farm wastes for rural industrial growth, National Dairy Research Institute, Bangalore, 31 st December, 1975.
This paper is published with the permission of the Director-General, Indian Council of Medical Research, New Delhi 相似文献
Résumé Dans 3 localités de Bangalore ou proches de cette ville, on a inventorié les espèces de mouches vivant dans le fumier de vache, leurs parasites et prédateurs ainsi que d'autres arthropodes associés. Les mouches récoltées sont:Musca domestica L.,Musca pattoni Austen,Stomoxys calcitrans L.,Physiphora aenea F.,Physiphora demandata F.,Sargus metallinus F.,Sepsis thoracica R-D.,Sepsis nitens Wiedemann,Sphaerocera scabricula Hal. etLeptocera (Coproica) hirtula Rondani. Quatre espèces d'hyménoptères parasites des pupes ont été obtenues de ces mouches:Spalangia cameroni Perkins deM. domestica, M. pattoni, S. calcitrans, P. aenea etP. demandata: Spalangia endius Walker deM. domestica, M. pattoni etS. calcitrans, P. aenea etP. demandata; Spalangia endius Walker trans; etDirhinus trichiophthalmus Masi deSargus metallinus F. On a noté le taux de parasitisme des nymphes dans les conditions naturelles. Quatre espèces deHister etAleochara puberula Klug s'attaquant aux divers stades non imaginaux deM. domestica, 2 espèces de scarabeides, 2 espèces de fourmis et un pseudoscorpion ont été également trouvés dans le fumier. L'importance de ces facteurs biotiques dans la régulation des populations de mouches est discutée.
Paper presented at the seminar on utilization of farm wastes for rural industrial growth, National Dairy Research Institute, Bangalore, 31 st December, 1975.
This paper is published with the permission of the Director-General, Indian Council of Medical Research, New Delhi 相似文献