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1.
Abstract The natural product cyanobacterin has been shown to be toxic to most cyanobacteria at a concentration of approx. 5 μM. We demonstrate here that cyanobacterin will also inhibit the growth of most eukaryotic algae at a similar concentration. Some algae, such as Euglena gracilis , are resistant because they are able to maintain themselves by heterotrophic nutrition. Others, such as Chlamydomonas reinhardtii , can apparently induce a detoxification mechanism to maintain photosynthesis in the presence of low concentrations of the inhibitor. Non-photosynthetic microorganisms are not affected by cyanobacterin. 相似文献
2.
The mortars covering some walls of the Roman city of Baelo Claudia (Cadiz, Spain) support an abundant colonization of cyanobacteria, algae and lichens. The distribution of these organisms is closely related to microclimatic parameters. Furthermore, the development, specific composition and biomass of algal cryptoendolithic communities are related to the wall orientation. The effect of these communities on mortar deterioration is discussed. 相似文献
3.
The unitary nature of the mitochondrion and the characteristic flattened finger-like morphology of the cristae were demonstrated in the Cryptophyceae. Hemiselmis rufescens contained an unbranched vermi-form mitochondrion in contrast to the variously branched complex, comprising an interconnected peripheral and central reticulum, in Chroomonas sp. and strains of Cryptomonas. The systematic value of the shape and distribution of the mitochondria in the examined genera was suggested. 相似文献
4.
ABSTRACTThis article reviews the role of microbial biofilms in infection, and the antimicrobial chemical diversity of marine macroalgae and their associated microbiomes. Antimicrobial resistance (AMR) represents one of the major health threats faced by humanity over the next few years. To prevent a global epidemic of antimicrobial-resistant infections, the discovery of new antimicrobials and antibiotics, better anti-infection strategies and diagnostics, and changes to our current use of antibiotics have all become of paramount importance. Numerous studies investigating the bioactivities of seaweed extracts as well as their secondary and primary metabolites highlight the vast biochemical diversity of seaweeds, with new modes of action making them ideal sources for the discovery of novel antimicrobial bioactive compounds of pharmaceutical interest. In recent years, researchers have focused on characterizing the endophytic and epiphytic microbiomes of various algal species in an attempt to elucidate host-microbe interactions as well as to understand the function of microbial communities. Although environmental and host-associated factors crucially shape microbial composition, microbial mutualistic and obligate symbionts are often found to play a fundamental role in regulating many aspects of host fitness involving ecophysiology and metabolism. In particular, algal ‘core’ epiphytic bacterial communities play an important role in the protection of surfaces from biofouling, pathogens and grazers through the production of bioactive metabolites. Together, marine macroalgae and their associated microbiomes represent unique biological systems offering great potential for the isolation and identification of novel compounds and strategies to counteract the rise and dissemination of AMR. 相似文献
5.
J.M.M. AdamsA.B. Ross K. AnastasakisE.M. Hodgson J.A. GallagherJ.M. Jones I.S. Donnison 《Bioresource technology》2011,102(1):226-234
To avoid negative impacts on food production, novel non-food biofuel feedstocks need to be identified and utilised. One option is to utilise marine biomass, notably fast-growing, large marine ‘plants’ such as the macroalgal kelps. This paper reports on the changing composition of Laminaria digitata throughout it growth cycle as determined by new technologies. The potential of Laminaria sp. as a feedstock for biofuel production and future biorefining possibilities was assessed through proximate and ultimate analysis, initial pyrolysis rates using thermo-gravimetric analysis (TGA), metals content and pyrolysis gas chromatography-mass spectrometry.Samples harvested in March contained the lowest proportion of carbohydrate and the highest ash and alkali metal content, whereas samples harvested in July contained the highest proportions of carbohydrate, lowest alkali metals and ash content. July was therefore considered the most suitable month for harvesting kelp biomass for thermochemical conversion to biofuels. 相似文献
6.
The new higher level classification of eukaryotes with emphasis on the taxonomy of protists 总被引:23,自引:0,他引:23
Adl SM Simpson AG Farmer MA Andersen RA Anderson OR Barta JR Bowser SS Brugerolle G Fensome RA Fredericq S James TY Karpov S Kugrens P Krug J Lane CE Lewis LA Lodge J Lynn DH Mann DG McCourt RM Mendoza L Moestrup O Mozley-Standridge SE Nerad TA Shearer CA Smirnov AV Spiegel FW Taylor MF 《The Journal of eukaryotic microbiology》2005,52(5):399-451
This revision of the classification of unicellular eukaryotes updates that of Levine et al. (1980) for the protozoa and expands it to include other protists. Whereas the previous revision was primarily to incorporate the results of ultrastructural studies, this revision incorporates results from both ultrastructural research since 1980 and molecular phylogenetic studies. We propose a scheme that is based on nameless ranked systematics. The vocabulary of the taxonomy is updated, particularly to clarify the naming of groups that have been repositioned. We recognize six clusters of eukaryotes that may represent the basic groupings similar to traditional "kingdoms." The multicellular lineages emerged from within monophyletic protist lineages: animals and fungi from Opisthokonta, plants from Archaeplastida, and brown algae from Stramenopiles. 相似文献
7.
8.
The Revised Classification of Eukaryotes 总被引:1,自引:0,他引:1
Sina M. Adl Alastair G. B. Simpson Christopher E. Lane Julius Lukeš David Bass Samuel S. Bowser Matthew W. Brown Fabien Burki Micah Dunthorn Vladimir Hampl Aaron Heiss Mona Hoppenrath Enrique Lara Line le Gall Denis H. Lynn Hilary McManus Edward A. D. Mitchell Sharon E. Mozley‐Stanridge Laura W. Parfrey Jan Pawlowski Sonja Rueckert Laura Shadwick Conrad L. Schoch Alexey Smirnov Frederick W. Spiegel 《The Journal of eukaryotic microbiology》2012,59(5):429-514
This revision of the classification of eukaryotes, which updates that of Adl et al. [J. Eukaryot. Microbiol. 52 (2005) 399], retains an emphasis on the protists and incorporates changes since 2005 that have resolved nodes and branches in phylogenetic trees. Whereas the previous revision was successful in re‐introducing name stability to the classification, this revision provides a classification for lineages that were then still unresolved. The supergroups have withstood phylogenetic hypothesis testing with some modifications, but despite some progress, problematic nodes at the base of the eukaryotic tree still remain to be statistically resolved. Looking forward, subsequent transformations to our understanding of the diversity of life will be from the discovery of novel lineages in previously under‐sampled areas and from environmental genomic information. 相似文献
9.
《Journal of biological education》2012,46(4):214-217
Department of Physiological Botany, Uppsala University, Uppsala, Sweden Hydrogen gas is regarded as a potential candidate for a future energy economy. Research and development in the field of hydrogen energy is greatly encouraged on all continents. A wide range of microorganisms are able to produce hydrogen gas, among them photosynthetically active organisms that use light as their sole energy source. These organisms are good candidates for the photobiological production of hydrogen gas. Green algae are of particular interest since they are capable of splitting water during photosynthesis and of releasing hydrogen gas under certain conditions. This article describes a small bioreactor that can be run in the classroom and used to demonstrate the concept of photohydrogen production. 相似文献
10.