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621.
Adnan Noor Shah Guozheng Yang Mohsin Tanveer Javaid Iqbal 《Acta Physiologiae Plantarum》2017,39(5):119
Nitrogen (N) rate and plant density (PD) are important factors for sustainable cotton production. The objective of this study is to examine the effects of nitrogen rate and plant density on plant growth, source–sink relationship, and cotton yield. A split-plot arrangement was used in the field experiment with the main plots assigned to N rate (120 and 180 kg/ha), and the sub-plots assigned to plant density (8, 10, and 12 plants/m2). Results showed significant N and PD interaction on plant growth, leaf gas exchange, and yield. Higher plant growth and cotton yield were noted under low nitrogen rate and high planting density than other treatment combinations. Leaf photosynthesis, stomatal conductance, intercellular CO2, transpiration rate, and water use efficiency were considerably influenced by planting density and nitrogen rate. Maximum values of these traits were obtained under low nitrogen rate with high planting density or high nitrogen rate with medium planting density, while the least values were under low nitrogen rate with low planting density. Correlation analysis revealed highly significant and positive relation between leaf gas exchange and cotton yield. 相似文献
622.
Reproductive interference by male Drosophila subobscura on female D. persimilis: A laboratory experiment
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Brenda Manzano‐Winkler Alexander J. Hish Emily K. Aarons Mohamed A. F. Noor 《Ecology and evolution》2017,7(7):2268-2272
While females often reject courtship attempts by heterospecific males, reproductive interference by harassment from such males can nonetheless occur, potentially reducing female fitness. Such effects may be profound following a range expansion, when males from a new species may suddenly encounter (and perhaps even become abundant relative to) females of related native species. Drosophila subobscura recently invaded North America and may impact native species through reproductive interference and other processes. We test for the potential for reproductive interference by D. subobscura males on D. persimilis females in the laboratory. D. subobscura males aggressively copulated with D. persimilis females, including many females that exhibit rejection behaviors. Despite females attempting to dismount the males, the heterospecific copulations are on average longer than conspecific copulations, and females exhibit some reluctance to remate with conspecific males following this harassment. Females confined with both conspecific and heterospecific males produce fewer adult progeny than those with either conspecific males only or with conspecific males and distantly related D. simulans males that do not engage in female harassment. Overall, our results illustrate how reproductive interference by an invasive species can have negative effects on resident natural populations. 相似文献
623.
Elad Noor Avi I. Flamholz Vijay Jayaraman Brian L. Ross Yair Cohen Wayne M. Patrick Ita GruicSovulj Dan S. Tawfik 《Protein science : a publication of the Protein Society》2022,31(8)
Enzymes are well known for their catalytic abilities, some even reaching “catalytic perfection” in the sense that the reaction they catalyze has reached the physical bound of the diffusion rate. However, our growing understanding of enzyme superfamilies has revealed that only some share a catalytic chemistry while others share a substrate‐handle binding motif, for example, for a particular phosphate group. This suggests that some families emerged through a “substrate‐handle‐binding‐first” mechanism (“binding‐first” for brevity) instead of “chemistry‐first” and we are, therefore, left to wonder what the role of non‐catalytic binders might have been during enzyme evolution. In the last of their eight seminal, back‐to‐back articles from 1976, John Albery and Jeremy Knowles addressed the question of enzyme evolution by arguing that the simplest mode of enzyme evolution is what they defined as “uniform binding” (parallel stabilization of all enzyme‐bound states to the same degree). Indeed, we show that a uniform‐binding proto‐catalyst can accelerate a reaction, but only when catalysis is already present, that is, when the transition state is already stabilized to some degree. Thus, we sought an alternative explanation for the cases where substrate‐handle‐binding preceded any involvement of a catalyst. We find that evolutionary starting points that exhibit negative catalysis can redirect the reaction''s course to a preferred product without need for rate acceleration or product release; that is, if they do not stabilize, or even destabilize, the transition state corresponding to an undesired product. Such a mechanism might explain the emergence of “binding‐first” enzyme families like the aldolase superfamily. 相似文献
624.
M. Norhayati S. Mohd Noor K. Chong A. W. Faizah D. F. Herridge M. B. Peoples F. J. Bergersen 《Plant and Soil》1988,108(1):143-150
Methods for partitioning the nitrogen assimilated by nodulated legumes, between nitrogen derived from soil sources and from
N2 fixation, are described as applied in peninsular Malaysia.
The analysis of nitrogenous components translocated from the roots to the shoots of nodulated plants in the xylem sap is outlined,
with some precautions to be observed for applications in the tropics. Some examples of the use of the technique in surverying
apparent N2 fixation by tropical legumes, in studying interrow cropping in plantation systems and in assessing effects of experimental
treatments on N2 fixation by food legumes, are described.
Techniques for assesing N2 fixation by means of15N abundance have been used to show that applications of nitrogenous fertilizers commonly used in Malaysia for soybeans depress
N2 fixation, that similar results are obtained with natural abundance and15N-enrichment methods and that, in at least two locations in Malaysia, differences between the natural abundance of15N in plant-available soil nitrogen and in atmospheric N2 are great enough to permit application to measurement of N2 fixation by leguminous crops. 相似文献
625.
An organic solvent-tolerant S5 lipase was purified by affinity chromatography and anion exchange chromatography. The molecular mass of the lipase was estimated to be 60 kDa with 387 purification fold. The optimal temperature and pH were 45 degrees C and 9.0, respectively. The purified lipase was stable at 45 degrees C and pH 6-9. It exhibited the highest stability in the presence of various organic solvents such as n-dodecane, 1-pentanol, and toluene. Ca2+ and Mg2+ stimulated lipase activity, whereas EDTA had no effect on its activity. The S5 lipase exhibited the highest activity in the presence of palm oil as a natural oil and triolein as a synthetic triglyceride. It showed random positional specificity on the thin-layer chromatography. 相似文献
626.
Nur Amira Khairil Anwar Muhammad Najmi Mohd Nazri Ahmad Hafiz Murtadha Elis Rosliza Mohd Adzemi Venugopal Balakrishnan Khairul Mohd Fadzli Mustaffa Tengku Ahmad Damitri AI-Astani Tengku Din Maya Mazuwin Yahya Juhara Haron Noor Fatmawati Mokhtar 《Acta biochimica et biophysica Sinica》2021,(8):961-978
Aggressive tissue biopsy is commonly unavoidable in the management of most suspected tumor cases to conclusively verify the presence of cancerous cells through ... 相似文献
627.
628.
Noor A. Yusuf Judith L. Green Richard J. Wall Ellen Knuepfer Robert W. Moon Christina Schulte-Huxel Rebecca R. Stanway Stephen R. Martin Steven A. Howell Christopher H. Douse Ernesto Cota Edward W. Tate Rita Tewari Anthony A. Holder 《The Journal of biological chemistry》2015,290(19):12147-12164
Myosin B (MyoB) is one of the two short class XIV myosins encoded in the Plasmodium genome. Class XIV myosins are characterized by a catalytic “head,” a modified “neck,” and the absence of a “tail” region. Myosin A (MyoA), the other class XIV myosin in Plasmodium, has been established as a component of the glideosome complex important in motility and cell invasion, but MyoB is not well characterized. We analyzed the properties of MyoB using three parasite species as follows: Plasmodium falciparum, Plasmodium berghei, and Plasmodium knowlesi. MyoB is expressed in all invasive stages (merozoites, ookinetes, and sporozoites) of the life cycle, and the protein is found in a discrete apical location in these polarized cells. In P. falciparum, MyoB is synthesized very late in schizogony/merogony, and its location in merozoites is distinct from, and anterior to, that of a range of known proteins present in the rhoptries, rhoptry neck or micronemes. Unlike MyoA, MyoB is not associated with glideosome complex proteins, including the MyoA light chain, myosin A tail domain-interacting protein (MTIP). A unique MyoB light chain (MLC-B) was identified that contains a calmodulin-like domain at the C terminus and an extended N-terminal region. MLC-B localizes to the same extreme apical pole in the cell as MyoB, and the two proteins form a complex. We propose that MLC-B is a MyoB-specific light chain, and for the short class XIV myosins that lack a tail region, the atypical myosin light chains may fulfill that role. 相似文献
629.
Anthony K. Campbell Graciela Sala-Newby Paul J. Aston Noor Kalsheker Yoshito Kishi Osamu Shimomura 《Luminescence》1990,5(2):131-139
The Luc gene from the firefly Photinus pyralis has been isolated by cloning it in pcDV1 PL plasmid primer and Honjo linker and the Phot gene isolated from Aequorea victoria using the polymerase chain reaction. A method has been established using SP6 RNA polymerase for transcribing and translating bioluminescent genes in vitro. It should now be possible to engineer these genes to measure intracellular ATP and the covalent modification of proteins in single, live cells, providing unique insights into the molecular basis of disease. 相似文献
630.
Wan Zakaria Wan Nor Adibah Aizat Wan Mohd Goh Hoe-Han Mohd Noor Normah 《Journal of plant research》2019,132(5):681-694
Journal of Plant Research - Carnivorous plants capture and digest insects for nutrients, allowing them to survive in soil deprived of nitrogenous nutrients. Plants from the genus Nepenthes produce... 相似文献