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1.
Twenty-four fungus isolates from the compost utilized in commercially growing Agaricus brunnescens were tested for their ability to produce extracellular enzymes involved in the degradation of cellulose, lignin and xylan, the major components of the straw of the compost. All 24 isolates were able to degrade carboxymethyl cellulose. Most were classified as weak or moderate producers of exo--glucanase. Twenty of the 24 were also able to hydrolyze filter paper, a crystalline cellulose. Nineteen of the 24 were able to hydrolyze xylan, a hemicellulose. The production of extracellular polyphenol oxidases was detected utilizing two tests; the blueing of alcoholic gum guaiacol, which indicates tyrosinase production, and the browning of malt extract-gallic acid agar, which indicates laccase production. Twenty produced tyrosinase, but only eight produced laccase. Agaricus brunnescens was also included in all of the tests. It produced exo--glucanase, hemicellulase, tyrosinase and lactase. 相似文献
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Eric Allan Wolfgang W. Weisser Markus Fischer Ernst-Detlef Schulze Alexandra Weigelt Christiane Roscher Jussi Baade Romain L. Barnard Holger Beßler Nina Buchmann Anne Ebeling Nico Eisenhauer Christof Engels Alexander J. F. Fergus Gerd Gleixner Marlén Gubsch Stefan Halle Alexandra M. Klein Ilona Kertscher Annely Kuu Markus Lange Xavier Le Roux Sebastian T. Meyer Varvara D. Migunova Alexandru Milcu Pascal A. Niklaus Yvonne Oelmann Esther Pašalić Jana S. Petermann Franck Poly Tanja Rottstock Alexander C. W. Sabais Christoph Scherber Michael Scherer-Lorenzen Stefan Scheu Sibylle Steinbeiss Guido Schwichtenberg Vicky Temperton Teja Tscharntke Winfried Voigt Wolfgang Wilcke Christian Wirth Bernhard Schmid 《Oecologia》2013,173(1):223-237
In order to predict which ecosystem functions are most at risk from biodiversity loss, meta-analyses have generalised results from biodiversity experiments over different sites and ecosystem types. In contrast, comparing the strength of biodiversity effects across a large number of ecosystem processes measured in a single experiment permits more direct comparisons. Here, we present an analysis of 418 separate measures of 38 ecosystem processes. Overall, 45 % of processes were significantly affected by plant species richness, suggesting that, while diversity affects a large number of processes not all respond to biodiversity. We therefore compared the strength of plant diversity effects between different categories of ecosystem processes, grouping processes according to the year of measurement, their biogeochemical cycle, trophic level and compartment (above- or belowground) and according to whether they were measures of biodiversity or other ecosystem processes, biotic or abiotic and static or dynamic. Overall, and for several individual processes, we found that biodiversity effects became stronger over time. Measures of the carbon cycle were also affected more strongly by plant species richness than were the measures associated with the nitrogen cycle. Further, we found greater plant species richness effects on measures of biodiversity than on other processes. The differential effects of plant diversity on the various types of ecosystem processes indicate that future research and political effort should shift from a general debate about whether biodiversity loss impairs ecosystem functions to focussing on the specific functions of interest and ways to preserve them individually or in combination. 相似文献
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JH Shazia Fathima Jayaraman Selvaraj Venkatacalam Sivabalan Umapathy Vidhya Rekha Rajagopal Ponnulakshmi Veeraraghavan Vishnupriya Malathi Kullappan Radhika Nalinakumari Sreekandan Surapaneni Krishna Mohan Periyasamy Vijayalakshmi 《Bioinformation》2021,17(1):212
The mTOR (mammalian or mechanistic Target of Rapamycin) is linked with oral cancer. Therefore, it is of interest to study the molecular docking-based binding of paclitaxel (a FDA approved drug for oral cancer) and its analogues with mTOR. Hence, we report the binding features of 10-Deacetyltaxol, 7-Epi-10-deacetyltaxol, 7-Epi-Taxol and 6alpha-Hydroxypaclitaxel with mTOR for further consideration. 相似文献
6.
Janine JH Oosterhof G Jolanda Elving Ietse Stokroos Arie van nieuw Amerongen Henny C van der Mei Henk J Busscher 《Biofouling》2013,29(6):347-353
The integrity of biofilms on voice prostheses used to rehabilitate speech in laryngectomized patients causes unwanted increases in airflow resistance, impeding speech. Biofilm integrity is ensured by extracellular polymeric substances (EPS). This study aimed to determine whether synthetic salivary peptides or mucolytics, including N-acetylcysteine and ascorbic acid, influence the integrity of voice prosthetic biofilms. Biofilms were grown on voice prostheses in an artificial throat model and exposed to synthetic salivary peptides, mucolytics and two different antiseptics (chlorhexidine and Triclosan). Synthetic salivary peptides did not reduce the air flow resistance of voice prostheses after biofilm formation. Although both chlorhexidine and Triclosan reduced microbial numbers on the prostheses, only the Triclosan-containing positive control reduced the air flow resistance. Unlike ascorbic acid, the mucolytic N-acetylcysteine removed most EPS from the biofilms and induced a decrease in air flow resistance. 相似文献
7.
Detecting non-neutral heterogeneity across a region of DNA sequence in the ratio of polymorphism to divergence 总被引:7,自引:4,他引:7
Natural selection, in the form of balancing selection or selective sweeps,
can result in a decoupling of the amounts of molecular polymorphism and
divergence. Thus natural selection can cause some areas of DNA sequence to
have greater silent polymorphism, relative to divergence between species,
than other areas. It would be useful to have a statistical test for
heterogeneity in the polymorphism to divergence ratio across a region of
DNA sequence, one that could identify heterogeneity greater than that
expected from the neutral processes of mutation, drift, and recombination.
The only currently available test requires that a region be arbitrarily
divided into sections that are compared with each other, and the
subjectivity of this division could be problematic. Here a test is proposed
in which runs of polymorphic and fixed sites are counted, where a "run" is
a set of one or more sites of one type preceded and followed by the other
type. The number of runs is smaller than otherwise expected if
polymorphisms are clumped together. By simulating neutral evolution and
comparing the observed number of runs to the simulations, a statistical
test is possible which does not require any a priori decisions about
subdivision.
相似文献
8.
One hundred and twenty-six strains of Bacillus thuringiensis representing 57 serovars were allocated to 58 genomic types using random amplified polymorphic DNA (RAPD)-PCR patterns. Serovars darmstadiensis, israelensis, kenyae, kumamotoensis, kurstaki, morrisoni, pakistani, sotto, thuringiensis and tolworthi each encompassed identical or closely related strains. Despite this genomic homogeneity, most of these serovars also included at least one variant strain. Serovars aizawai, canadensis, entomocidus and sotto biotype dendrolimus, on the other hand, were genomically heterogeneous. Of the 57 serovars examined, 31 contained at least one strain with a closely related or identical RAPD pattern to a strain from a different serovar. We conclude that while the species is genomically diverse, the homogeneous serovars represent clonal lineages of successful insect pathogens. 相似文献
9.
Fergus P. Meehan Arvind S. Moolgaoker John Stallworthy 《BMJ (Clinical research ed.)》1972,2(5816):740-742
In the absence of a recurring indication for caesarean section vaginal delivery in subsequent pregnancy is a “trial of scar,” with potentially serious implications for mother and baby. Labour under caudal analgesia was carefully supervised for 75 women with a surgically scarred uterus—due to lower segment section in 72, abdominal hysterotomy in one, and transcavity myomectomy in two. Every caesarean scar was assessed digitally during labour and every uterus was examined after delivery. Caudal analgesia provided a painless labour and delivery and made scar assessment easy. Controlled intravenous Syntocinon infusion was given to 25 patients. One scar dehiscence occurred early in labour and one in the second stage. Seventy mothers had 71 vaginal deliveries with one pair of twins and one breech. There was one stillbirth and no neonatal death. There were five repeat sections. 相似文献
10.
Mario A. Cepeda Jacob JH. Pelling Caitlin L. Evered Hon S. Leong Sashko Damjanovski 《Experimental cell research》2017,350(1):169-183
Membrane-type-1 Matrix Metalloproteinase (MT1-MMP) is a multifunctional protease that regulates ECM degradation, proMMP-2 activation, and varied cellular processes including migration and viability. MT1-MMP is believed to be a central mediator of tumourigenesis whose role is dictated by its functionally distinct protein domains. Both the localization and signal transduction capabilities of MT1-MMP are dependent on its cytoplasmic domain, exemplifying diverse regulatory functions. To further our understanding of the multifunctional contributions of MT1-MMP to cellular processes, we overexpressed cytoplasmic domain altered constructs in MCF-7 breast cancer cells and analyzed migration and viability in 2D culture conditions, morphology in 3D Matrigel culture, and tumorigenic ability in vivo. We found that the cytoplasmic domain was not needed for MT1-MMP mediated migration promotion, but was necessary to maintain viability during serum depravation in 2D culture. Similarly, during 3D Matrigel culture the cytoplasmic domain of MT1-MMP was not needed to initiate a protrusive phenotype, but was necessary to prevent colony blebbing when cells were serum deprived. We also tested in vivo tumorigenic potential to show that cells expressing cytoplasmic domain altered constructs demonstrated a reduced ability to vascularize tumours. These results suggest that the cytoplasmic domain regulates MT1-MMP function in a manner required for cell survival, but is dispensable for cell migration. 相似文献