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71.
Analysis of the chloroplast protein complexes by blue-native polyacrylamide gel electrophoresis (BN-PAGE) 总被引:5,自引:0,他引:5
Kügler Marion Jänsch Lothar Kruft Volker Schmitz Udo K. Braun Hans-Peter 《Photosynthesis research》1997,53(1):35-44
Blue-native polyacrylamide gel electrophoresis (BN-PAGE) is a powerful procedure for the separation and characterization of the protein complexes from mitochondria. Membrane proteins are solubilized in the presence of aminocaproic acid and n-dodecylmaltoside and Coomassie-dyes are utilized before electrophoresis to introduce a charge shift on proteins. Here, we report a modification of the procedure for the analysis of chloroplast protein complexes. The two photosystems, the light-harvesting complexes, the ATP synthase, the cytochrome b
6
f complex and the ribulose-bisphosphate carboxylase/oxygenase are well resolved. Analysis of the protein complexes on a second gel dimension under denaturing conditions allows separation of more than 50 different proteins which are part of chloroplast multi-subunit enzymes. The resolution capacity of the blue-native gels is very high if compared to 'native green gel systems' published previously. N-terminal amino acid sequences of single subunits can be directly determined by cyclic Edman degradation as demonstrated for eight proteins. Analysis of chloroplast protein complexes by blue-native gel electrophoresis will allow the generation of 'protein maps' from different species, tissues and developmental stages or from mutant organelles. Further applications of blue-native gel electrophoresis are discussed. 相似文献
72.
Katja?Witzel Christof?Pietsch Marc?Strickert Andrea?Matros Marion?S.?R?der Winfriede?Weschke Ulrich?Wobus Hans-Peter?MockEmail author 《Molecular breeding : new strategies in plant improvement》2011,27(3):301-314
Barley (Hordeum vulgare) is an important cereal crop grown for both the feed and malting industries. Hence, there is great interest to gain deeper
insight into the determinants of grain nutritional quality in order to improve the assessment of new traits. Two-dimensional
gel electrophoresis was employed for the characterization of the grain proteome of doubled-haploid introgression lines (IL)
representing a wild barley genome (Hordeum spontaneum Hs213) within a modern cultivar background (H. vulgare cv. Brenda). Proteome maps were subjected to differential cluster analysis and revealed ILs with similar or different protein
expression patterns compared to the Brenda parent. A total of 51 quantitative trait loci for protein expression (pQTL) were
detected, and proteins underlying these pQTL were further examined by mass spectrometry. Identification was successful for
49 of the segregating spots and functional annotation of proteins revealed that most proteins are involved in metabolism and
disease/defence-related processes. Among those, multigene families of glyceraldehyde-3-phosphate dehydrogenases, heat shock
proteins, peroxidases, and serpins were identified. Overall, eight pQTL signals were discovered in two independently grown
sets of plants. The mapped spots included protein disulfide isomerase, α-amylase inhibitor BDAI, NADP malic enzyme, adenosine
kinase and peroxidase BP1. Specific marker information of proteins involved in developmental events and protein storage as
well as in disease- and defence-related processes now allows for targeted breeding approaches to improve the grain quality
in barley. 相似文献
73.
Rebecca S. Williams Jana H. Stollings ?ucja Bundy Regine Haard?rfer Matthew W. Kreuter Patricia Dolan Mullen Mel Hovell Marti Morris Michelle C. Kegler 《PloS one》2016,11(11)
This study examined the extent to which delivery of the minimal Smoke-Free Homes intervention by trained 2-1-1 information and referral specialists had an effect on the adoption of home smoking bans in low-income households. A randomized controlled trial was conducted among 2-1-1 callers (n = 500) assigned to control or intervention conditions. 2-1-1 information and referral specialists collected baseline data and delivered the intervention consisting of 3 mailings and 1 coaching call; university-based data collectors conducted follow-up interviews at 3 and 6 months post-baseline. Data were collected from June 2013 through July 2014. Participants were mostly female (87.2%), African American (61.4%), and smokers (76.6%). Participants assigned to the intervention condition were more likely than controls to report a full ban on smoking in the home at both 3- (38.1% vs 19.3%, p = < .001) and 6-month follow-up (43.2% vs 33.2%, p = .02). The longitudinal intent-to-treat analysis showed a significant intervention effect over time (OR = 1.31, p = .001), i.e. OR = 1.72 at 6 months. This study replicates prior findings showing the effectiveness of the minimal intervention to promote smoke-free homes in low-income households, and extends those findings by demonstrating they can be achieved when 2-1-1 information and referral specialists deliver the intervention. Findings offer support for this intervention as a generalizable and scalable model for reducing secondhand smoke exposure in homes. 相似文献
74.
Rafika Saker Noureddine Bouras Abdelghani Zitouni Mostefa Ghoul Manfred Rohde Peter Schumann Cathrin Spröer Nasserdine Sabaou Hans-Peter Klenk 《Antonie van Leeuwenhoek》2014,106(5):1021-1030
Three halophilic mycelium-forming actinobacteria, strains H195T, H150 and H151, were isolated from a Saharan soil sample collected from Béni-isguen in the Mzab region (Ghardaïa, South of Algeria) and subjected to a polyphasic taxonomic characterisation. These strains were observed to show an aerial mycelium differentiated into coccoid spore chains and fragmented substrate mycelium. Comparative analysis of the 16S rRNA gene sequences revealed that the highest sequence similarities were to Saccharopolyspora qijiaojingensis YIM 91168T (92.02 % to H195T). Phylogenetic analyses showed that the strains H195T, H150 and H151 represent a distinct phylogenetic lineage. The cell-wall hydrolysate was found to contain meso-diaminopimelic acid, and the diagnostic whole-cell sugars were identified as arabinose and galactose. The major cellular fatty acids were identified as iso-C15:0, iso-C16:0, iso-C17:0 and anteiso-C17:0. The diagnostic phospholipid detected was phosphatidylcholine and MK-9 (H4) was found to be the predominant menaquinone. The genomic DNA G+C content of strain H195T was 68.2 mol%. On the basis of its phenotypic features and phylogenetic position, we propose that strain H195T represents a novel genus and species, Mzabimyces algeriensis gen. nov., sp. nov., within a new family, Mzabimycetaceae fam. nov. The type strain of M. algeriensis is strain H195T (=DSM 46680T = MTCC 12101T). 相似文献
75.
Stephanie Busch Aimo Kannt Matthias Kolibabka Andreas Schlotterer Qian Wang Jihong Lin Yuxi Feng Sigrid Hoffmann Norbert Gretz Hans-Peter Hammes 《PloS one》2014,9(7)
Rats expressing a transgenic polycystic kidney disease (PKD) gene develop photoreceptor degeneration and subsequent vasoregression, as well as activation of retinal microglia and macroglia. To target the whole neuroglialvascular unit, neuro- and vasoprotective Erythropoietin (EPO) was intraperitoneally injected into four –week old male heterozygous PKD rats three times a week at a dose of 256 IU/kg body weight. For comparison EPO-like peptide, lacking unwanted side effects of EPO treatment, was given five times a week at a dose of 10 µg/kg body weight. Matched EPO treated Sprague Dawley and water-injected PKD rats were held as controls. After four weeks of treatment the animals were sacrificed and analysis of the neurovascular morphology, glial cell activity and pAkt localization was performed. The number of endothelial cells and pericytes did not change after treatment with EPO or EPO-like peptide. There was a nonsignificant reduction of migrating pericytes by 23% and 49%, respectively. Formation of acellular capillaries was significantly reduced by 49% (p<0.001) or 40% (p<0.05). EPO-treatment protected against thinning of the central retina by 10% (p<0.05), a composite of an increase of the outer nuclear layer by 12% (p<0.01) and in the outer segments of photoreceptors by 26% (p<0.001). Quantification of cell nuclei revealed no difference. Microglial activity, shown by gene expression of CD74, decreased by 67% (p<0.01) after EPO and 36% (n.s.) after EPO-like peptide treatment. In conclusion, EPO safeguards the neuroglialvascular unit in a model of retinal neurodegeneration and secondary vasoregression. This finding strengthens EPO in its protective capability for the whole neuroglialvascular unit. 相似文献
76.
77.
Malaria remains one of the leading causes of death worldwide, despite decades of public health efforts. The recent commitment by many endemic countries to eliminate malaria marks a shift away from programs aimed at controlling disease burden towards one that emphasizes reducing transmission of the most virulent human malaria parasite, Plasmodium falciparum. Gametocytes, the only developmental stage of malaria parasites able to infect mosquitoes, have remained understudied, as they occur in low numbers, do not cause disease, and are difficult to detect in vivo by conventional methods. Here, we review the transmission biology of P. falciparum gametocytes, featuring important recent discoveries of genes affecting parasite commitment to gametocyte formation, microvesicles enabling parasites to communicate with each other, and the anatomical site where immature gametocytes develop. We propose potential parasite targets for future intervention and highlight remaining knowledge gaps. 相似文献
78.
Martin Gorges Hans-Peter Müller Dorothée Lulé Kelly Del Tredici Johannes Brettschneider Jürgen Keller Katharina Pfandl Albert C. Ludolph Jan Kassubek Elmar H. Pinkhardt 《PloS one》2015,10(11)
Background
The neuropathological process underlying amyotrophic lateral sclerosis (ALS) can be traced as a four-stage progression scheme of sequential corticofugal axonal spread. The examination of eye movement control gains deep insights into brain network pathology and provides the opportunity to detect both disturbance of the brainstem oculomotor circuitry as well as executive deficits of oculomotor function associated with higher brain networks.Objective
To study systematically oculomotor characteristics in ALS and its underlying network pathology in order to determine whether eye movement deterioration can be categorized within a staging system of oculomotor decline that corresponds to the neuropathological model.Methods
Sixty-eight ALS patients and 31 controls underwent video-oculographic, clinical and neuropsychological assessments.Results
Oculomotor examinations revealed increased anti- and delayed saccades’ errors, gaze-palsy and a cerebellary type of smooth pursuit disturbance. The oculomotor disturbances occurred in a sequential manner: Stage 1, only executive control of eye movements was affected. Stage 2 indicates disturbed executive control plus ‘genuine’ oculomotor dysfunctions such as gaze-paly. We found high correlations (p<0.001) between the oculomotor stages and both, the clinical presentation as assessed by the ALS Functional Rating Scale (ALSFRS) score, and cognitive scores from the Edinburgh Cognitive and Behavioral ALS Screen (ECAS).Conclusions
Dysfunction of eye movement control in ALS can be characterized by a two-staged sequential pattern comprising executive deficits in Stage 1 and additional impaired infratentorial oculomotor control pathways in Stage 2. This pattern parallels the neuropathological staging of ALS and may serve as a technical marker of the neuropathological spreading. 相似文献79.
80.