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61.
中国(竹思)簩竹属(Schizostachyum Nees)的研究及其它 总被引:3,自引:0,他引:3
夏念和 《热带亚热带植物学报》1993,1(1):1-10
对国产(竹思)(竹劳)竹属(Schizostachyum Nees)进行了系统整理。对属的范围进行了修订,认为本属应包括乔草竹属(Dendrochloa Parkinson),薄竹属(Leptocanna Chia et H.L.Fung),长穗竹属(Teinostachyum Munro)和李海竹属(Neohouzeaua A.Camus),并首次建立了本属的属下分类系统。此外,对二种竹子起了新名:甲竹(Bambusa austro-sinensis Xia)和毛环单竹(B.yunnanensis Xia);作了4个新组合,即Schizostachyum coradatum(Wen et Dai)Xia, S.dumetorum(Hance)Munro var.xinwuense(Wen et J. Y Chin)Xia, Bambusa glaucescens glaucescens(Willd)Sieb. ex Munro var.annulata(W.T.Lin et Z.J.Feng)Xia和B.glaucescens (Willd)Sieb.ex Munro var.pubivagina(W.T.... 相似文献
62.
Siyuan Zhang Jinhong Kan Xin Liu Yao Wu Mingyang Zhang Jinqing Ou Juan Wang Lin An Defeng Li Li Wang Xiu-Jie Wang Rongxiang Fang Yantao Jia 《Molecular Plant Pathology》2023,24(4):359-373
Chemical signal-mediated biological communication is common within bacteria and between bacteria and their hosts. Many plant-associated bacteria respond to unknown plant compounds to regulate bacterial gene expression. However, the nature of the plant compounds that mediate such interkingdom communication and the underlying mechanisms remain poorly characterized. Xanthomonas campestris pv. campestris (Xcc) causes black rot disease on brassica vegetables. Xcc contains an orphan LuxR regulator (XccR) which senses a plant signal that was validated to be glucose by HPLC-MS. The glucose concentration increases in apoplast fluid after Xcc infection, which is caused by the enhanced activity of plant sugar transporters translocating sugar and cell-wall invertases releasing glucose from sucrose. XccR recruits glucose, but not fructose, sucrose, glucose 6-phosphate, and UDP-glucose, to activate pip expression. Deletion of the bacterial glucose transporter gene sglT impaired pathogen virulence and pip expression. Structural prediction showed that the N-terminal domain of XccR forms an alternative pocket neighbouring the AHL-binding pocket for glucose docking. Substitution of three residues affecting structural stability abolished the ability of XccR to bind to the luxXc box in the pip promoter. Several other XccR homologues from plant-associated bacteria can also form stable complexes with glucose, indicating that glucose may function as a common signal molecule for pathogen–plant interactions. The conservation of a glucose/XccR/pip-like system in plant-associated bacteria suggests that some phytopathogens have evolved the ability to utilize host compounds as virulence signals, indicating that LuxRs mediate an interkingdom signalling circuit. 相似文献
63.
Cheng Jianxin Xia Yuqing Zhou Cheng Li Xiaohao Liu Pengfei 《Marine biotechnology (New York, N.Y.)》2023,25(2):291-313
Marine Biotechnology - Takifugu rubripes is important commercially fish species in China and it is under serious threat from white spot disease (cyptocaryoniasis), which leads to heavy economic... 相似文献
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Cnidarians are phylogenetically located near the base of the ‘tree of animals’, and their early evolution had a profound impact on the rise of bilaterians. However, the early diversity and phylogeny of this ‘lowly’ metazoan clade has hitherto been enigmatic. Fortunately, cnidarian fossils from the early Cambrian could provide key insights into their evolutionary history. Here, based on a scrutiny of the purported hyolith Burithes yunnanensis Hou et al. from the early Cambrian Chengjiang biota in South China, we reveal that this species shows characters distinct from those typical of hyoliths, not least a funnel-shaped gastrovascular system with a single opening, a whorl of tentacles surrounding the mouth, and the lack of an operculum. These characters suggest a great deviation from the original definition of the genus Burithes, and a closer affinity with cnidarians. We therefore reassign the material to a new genus: Palaeoconotuba. Bayesian inference of phylogeny based on new anatomical traits identifies a new clade, including Palaeoconotuba and Cambrorhytium, as a stem group of sessile medusozoan cnidarians that are united by the synapomorphies of developing an organic conical theca and a funnel-like gastrovascular system. This study unveils a stem lineage of medusozoans that evolved a lifelong conical theca in the early Cambrian. 相似文献
68.
Glycoprotein 330 (Gp330) is a member of the low-density lipoprotein receptor gene family that is expressed in the kidney. We have mapped the Gp330 gene to mouse chromosome 2, 4.5 cM proximal to Acra, in an interspecific backcross of (C57BL/6J × Mus spretus) F1 × C57BL/6J. 相似文献
69.
Xia Jun Hao Xianzhe Wang Tangang Li Huiqin Shi Xiaojuan Liu Yongchang Luo Honghai 《Journal of Plant Growth Regulation》2023,42(1):319-334
Journal of Plant Growth Regulation - Exogenous substances play an important role in the response of cotton to low-temperature conditions during the germination stage, but little is known about the... 相似文献
70.
别藻蓝蛋白藻蓝胆素发色团分子构象研究 总被引:1,自引:0,他引:1
主要研究了蓝绿藻污棕席藻(Phormidium luridum)别藻蓝蛋白在不同 pH值条件下的吸收光谱和共振拉曼光谱.发现低聚化的结果导致了三聚体别藻蓝蛋白 650nm 特征吸收峰的消失和一些共振拉曼带强度和位置的移动.结果表明在低 pH 值作用下的低聚化的别藻蓝蛋白中藻蓝胆素发色团分子的构象和自由胆素分子类似,比三聚体的别藻蓝蛋白的发色团分子更趋于卷曲,折叠的构象态.而三聚体的别藻蓝蛋白,主要的拉曼带 1645cm-1是其发色团分子构象处于更线性延展的标志,其光谱行为和吸收光谱 Avis/Auv所表征的发色团分子构象的结果相一致. 相似文献