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151.
152.
153.
C S Liu 《Journal of biochemistry》1975,78(1):19-29
One of the 2 main hemoglobins of the sea snake Pelamis platurus, (the Yellow-bellied sea snake) comprising about 70% of the total hemoglobin, was separated by DEAE-Sephadex column chromatography. From results of gel filtration and iron content determination, both intact sea snake hemoglobin, and the isolated major hemoglobin, were concluded to be composed of 4 subunits with a molecular weight of 66,000-67,000 daltons. Separation of the chains of globin of the major hemoglobin by CM 52 column chromatography gave 3 peaks, named, chains a, b, and c. The approximate molecular weights of chains a, b, and c were deduced by SDS gel electrophoresis to be 14,000, 16,000, and 20,000 daltons, respectively. The peptide maps and amino acid compositions of the three chains were distinctly different. N-Terminal and C-terminal amino acid sequence studies reveal that chains a, b, and c represented the alpha-chain, beta-chain, and beta'-chain differing from the normal beta-chain in having a C-terminal sequence of -Arg-Leu-His-Tyr. From the peak areas of the 3 chains obtained by CM 52 column chromatography, and the peak sizes of the 3 bands separated by SDS gel electrophoresis, it was concluded that the sea snake hemoglobin is composed of a hybrid tetramer, alpha2betabeta'. 相似文献
154.
Guno Haskå 《Microbial ecology》1975,1(1):234-245
Myxobacteria presumably produce extracellular bacteriolytic enzymes when they are growing in soil. In order to study their ecological significance, adsorption experiments were performed with lytic enzymes produced byMyxococcus virescens in casitone media. Different soils as well as montmorillonite and kaolinite can rapidly adsorb the bacteriolytic but not the proteolytic enzymes. About 1 gm of montmorillonite per liter of cell-free culture solution is enough for the adsorption of 97% of the bacteriolytic enzymes. The adsorption per unit weight is about 100 times greater on montmorillonite than on kaolinite. About 40% of the adsorbed enzymes can be eluted with solutions of high pH or high ionic strength. The only desorbed bacteriolytic enzyme is the alanyl-∈-N-lysine endopeptidase. 相似文献
155.
Jiaming Tian Bingxin Dai Li Gong Pingping Wang Han Ding Siwei Xia Weice Sun Cuiping Ren Jijia Shen Miao Liu 《PLoS neglected tropical diseases》2022,16(8)
Schistosomiasis is a serious and widespread parasitic disease caused by infection with Schistosoma. Because the parasite’s eggs are primarily responsible for schistosomiasis dissemination and pathogenesis, inhibiting egg production is a potential approach to control the spread and severity of the disease. The bromodomain and extra-terminal (BET) proteins represent promising targets for the development of epigenetic drugs against Schistosoma. JQ-1 is a selective inhibitor of the BET protein family. In the present study, JQ-1 was applied to S. japonicum in vitro. By using laser confocal scanning microscopy and EdU incorporation assays, we showed that application of JQ-1 to worms in vitro affected egg laying and the development of both the male and female reproductive systems. JQ-1 also inhibited the expression of the reproductive-related genes SjPlk1 and SjNanos1 in S. japonicum. Mice infected with S. japonicum were treated with JQ-1 during egg granuloma formation. JQ-1 treatment significantly reduced the size of the liver granulomas and levels of serum alanine aminotransferase and aspartate aminotransferase in mice and suppressed both egg laying and the development of male and female S. japonicum reproductive systems in vivo. Moreover, the mRNA expression levels of some proinflammatory cytokines were decreased in the parasites. Our findings suggest that JQ-1 treatment attenuates S. japonicum egg–induced hepatic granuloma due at least in part to suppressing the development of the reproductive system and egg production of S. japonicum. These findings further suggest that JQ-1 or other BET inhibitors warrant additional study as a new approach for the treatment or prevention of schistosomiasis. 相似文献
156.
Pengfei Li Liming Ruan Ruofan Wang Tianqi Liu Gao Song Xiaofei Gao Guohua Jiang Xiaoyan Liu 《仿生工程学报(英文版)》2021,18(6):1378-1390
Nanofibers(NFs)have been widely used in tissue engineering such as wound healing.In this work,the antibacterial ZnO quantum dots(ZnO QDs)have been incorporated into the biocompatible poly(ε-caprolactone)/collagen(PCL/Col)fibrous scaffolds for wound healing.The as-fabricated PCL-Col/ZnO fibrous scaffolds exhibited good swelling,antibacterial activity,and biodegradation behaviors,which were beneficial for the applications as a wound dressing.Moreover,the PCL-Col/ZnO fibrous scaffolds showed excellent cytocompatibility for promoting cell proliferation.The resultant PCL-Col/ZnO fibrous scaffolds containing vascular endothelial growth factor(VEGF)also exhibited promoted wound-healing effect through promoting expression of transforming growth factor-β(TGF-β)and the vascular factor(CD31)in tissues in the early stages of wound healing.This new electrospun fibrous scaffolds with wound-healing promotion and antibacterial property should be convenient for treating wound healing. 相似文献
157.
Shuai Ma Shuhui Sun Jiaming Li Yanling Fan Jing Qu Liang Sun Si Wang Yiyuan Zhang Shanshan Yang Zunpeng Liu Zeming Wu Sheng Zhang Qiaoran Wang Aihua Zheng Shuguang Duo Yang Yu Juan Carlos Izpisua Belmonte Piu Chan Qi Zhou Moshi Song Weiqi Zhang Guang-Hui Liu 《Cell research》2021,(4):415-432
Aging is a major risk factor for many diseases,especially in highly prevalent cardiopulmonary comorbidities and infectious diseases including Coronavirus Diseas... 相似文献
158.
XiaoLong Lin Zheng Liu LiPing Yan Xin Duan WenJun Bu XinHua Wang ChenGuang Zheng 《Ecology and evolution》2022,12(5)
Mitogenomes have been widely used for phylogenetic reconstruction of various Dipteran groups, but specifically for chironomid, they have not been carried out to resolve the relationships. Diamesinae (Diptera: Chironomidae) are important bioindicators for freshwater ecosystem monitoring, but its evolutionary history remains uncertain for lack of information. Here, coupled with one previously published and 30 new mitogenomes of Diamesinae, we carried out comparative mitogenomic analysis and phylogenetic analysis. Mitogenomes of Diamesinae were conserved in structure, and all genes arranged in the same order as the ancestral insect mitogenome. All protein‐coding genes in Diamesinae were under stronger purifying selection than those of other nonbiting midge species, which may exhibit signs of adaptation to life at cold living conditions. Phylogenetic analyses strongly supported the monophyly of Diamesinae, with Boreheptagyiini deeply nested within Diamesini. In addition, phylogenetic relationship of selected six genera was resolved, except Sympotthastia remained unstable. Our study revealed that the mitogenomes of Diamesinae are highly conserved, and they are practically useful for phylogenetic inference. 相似文献
159.
Wanzhen Liu David A. S. Smith Gayatri Raina Rowan Stanforth Ivy Ng'Iru Piera Ireri Dino J. Martins Ian J. Gordon Simon H. Martin 《Biology letters》2022,18(6)
Warning coloration provides a textbook example of natural selection, but the frequent observation of polymorphism in aposematic species presents an evolutionary puzzle. We investigated biogeography and polymorphism of warning patterns in the widespread butterfly Danaus chrysippus using records from citizen science (n = 5467), museums (n = 8864) and fieldwork (n = 2586). We find that polymorphism in three traits controlled by known mendelian loci is extensive. Broad allele frequency clines, hundreds of kilometres wide, suggest a balance between long-range dispersal and predation of unfamiliar morphs. Mismatched clines for the white hindwing and forewing tip in East Africa are consistent with a previous finding that the black wingtip allele has spread recently in the region through hitchhiking with a heritable endosymbiont. Light/dark background coloration shows more extensive polymorphism. The darker genotype is more common in cooler regions, possibly reflecting a trade-off between thermoregulation and predator warning. Overall, our findings show how studying local adaptation at the global scale provides a more complete picture of the evolutionary forces involved. 相似文献
160.