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Xanthomonadales
The Xanthomonadales are a bacterial order within the Gammaproteobacteria. They are one of the largest groups of bacterial phytopathogens, harbouring species such as ''Xanthomonas citri'', '' Xanthomonas euvesicatoria'', ''Xanthomonas oryzae'' and '' Xylella fastidiosa''. These bacteria affect agriculturally important plants including tomatoes, bananas, citrus plants, rice, and coffee. Species within the genus '' Stenotrophomonas'' are multidrug resistant opportunistic pathogens that are responsible for nosocomial infections in immunodeficient patients. Characteristics The Xanthomonadales are gram-negative, catalase positive, non-spore forming obligate aerobes.Saddler GS, Bradbury JF (2005) Order III. Xanthomonadales ord. nov. In: Bergey’s Manual of Systematic Bacteriology. pp. 63-122. Eds Brenner DJ, Krieg NR, Staley JT, Garrity GM, Boone, Vos P, Goodfellow M, Rainey FA, Schleifer K-H Springer-: Austin. Members belonging to the order are straight rods lacking prosthecae. W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conserved Signature Indels
Conserved signature inserts and deletions (CSIs) in protein sequences provide an important category of molecular markers for understanding phylogenetic relationships. CSIs, brought about by rare genetic changes, provide useful phylogenetic markers that are generally of defined size and they are flanked on both sides by conserved regions to ensure their reliability. While indels can be arbitrary inserts or deletions, CSIs are defined as only those protein indels that are present within conserved regions of the protein. The CSIs that are restricted to a particular clade or group of species, generally provide good phylogenetic markers of common evolutionary descent. Due to the rarity and highly specific nature of such changes, it is less likely that they could arise independently by either Convergent evolution, convergent or parallel evolution (i.e. homoplasy) and therefore are likely to represent synapomorphy. Other confounding factors such as differences in evolutionary rates at dif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xanthomonadaceae
Xanthomonadaceae is a family of Pseudomonadota within the order Xanthomonadales The Xanthomonadales are a bacterial order within the Gammaproteobacteria. They are one of the largest groups of bacterial phytopathogens, harbouring species such as ''Xanthomonas citri'', '' Xanthomonas euvesicatoria'', ''Xanthomonas oryzae'' an .... It was previously known as Lysobacteraceae. References External links National J.P. Euzéby: List of Prokaryotic names with Standing in Nomenclature (LPSN) {{gammaproteobacteria-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhodanobacteraceae
Rhodanobacteraceae is a family of bacteria of the order Xanthomonadales. The type genus In biological taxonomy, the type genus (''genus typica'') is the genus which defines a biological family and the root of the family name. Zoological nomenclature According to the International Code of Zoological Nomenclature, "The name-bearin ... is Rhodanobacter. References Xanthomonadales Bacteria families {{Gammaproteobacteria-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gammaproteobacteria
''Gammaproteobacteria'' is a class of bacteria in the phylum ''Pseudomonadota'' (synonym ''Proteobacteria''). It contains about 250 genera, which makes it the most genus-rich taxon of the Prokaryotes. Several medically, ecologically, and scientifically important groups of bacteria belong to this class. All members of this class are Gram-negative. It is the most phylogenetically and physiologically diverse class of the ''Pseudomonadota''. Members of ''Gammaproteobacteria'' live in several terrestrial and marine environments, in which they play various important roles, including in extreme environments such as hydrothermal vents. They can have different shapes, rods, curved rods, cocci, spirilla, and filaments, and include free living bacteria, biofilm formers, commensals and symbionts; some also have the distinctive trait of being bioluminescent. Diverse metabolisms are found in ''Gammaproteobacteria''; there are both aerobic and anaerobic (obligate or facultative) species, chem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stenotrophomonas
''Stenotrophomonas'' is a genus of Gram-negative bacteria, comprising at least twenty-six species. The main reservoirs of ''Stenotrophomonas'' are soil and plants. ''Stenotrophomonas'' species range from common soil organisms (''S. nitritireducens'') to opportunistic human pathogens ('' S. maltophilia''); the taxonomy of the genus is still somewhat unclear. Importance The most common species, ''S. maltophilia'', is very versatile and can be beneficial for plant growth and health, can be used in agriculture, biocontrol, bioremediation and phytoremediation strategies as well as the production of biomolecules of economic value. On the other hand, some of '' S. maltophilia'' strains are opportunistic pathogens to humans with a multidrug resistant profile. ''S. indologenes'' can also cause or be part of polymicrobial infections in humans, especially small children. Most ''Stenotrophomonas'' generally are not phytopathogenic unlike closely related genera '' Xylella'' and ''Xanthomo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xylella Fastidiosa
''Xylella fastidiosa'' is an aerobic, Gram-negative bacterium of the genus ''Xylella''. It is a plant pathogen, that grows in the water transport tissues of plants ( xylem vessels) and is transmitted exclusively by xylem sap-feeding insects such as sharpshooters and spittlebugs. Many plant diseases are due to infections of ''X. fastidiosa'', including bacterial leaf scorch, oleander leaf scorch, coffee leaf scorch (CLS), alfalfa dwarf, phony peach disease, and the economically important Pierce's disease of grapes (PD), olive quick decline syndrome (OQDS), and citrus variegated chlorosis (CVC). While the largest outbreaks of ''X. fastidiosa''–related diseases have occurred in the Americas and Europe, this pathogen has also been found in Taiwan, Israel, and a few other countries worldwide. ''Xylella fastidiosa'' can infect an extremely wide range of plants, many of which do not show any symptoms of disease. Disease occurs in plant species that are susceptible due to bloc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacillus (shape)
Bacterial cellular morphologies are the shapes that are characteristic of various types of bacteria and often key to their identification. Their direct examination under a light microscope enables the classification of these bacteria (and archaea). Generally, the basic morphologies are spheres (coccus) and round-ended cylinders or rod shaped (bacillus). But, there are also other morphologies such as helically twisted cylinders (example '' Spirochetes''), cylinders curved in one plane (selenomonads) and unusual morphologies (the square, flat box-shaped cells of the Archaean genus '' Haloquadratum)''. Other arrangements include pairs, tetrads, clusters, chains and palisades. Types Coccus A coccus (plural ''cocci'', from the Latin ''coccinus'' (scarlet) and derived from the Greek ''kokkos'' (berry)), is any microorganism (usually bacteria) whose overall shape is spherical or nearly spherical. Coccus refers to the shape of the bacteria and can contain multiple genera, such as st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prosthecate Bacteria
Prosthecate bacteria are a non-phylogenetically related group of Gram-negative bacteria that possess appendages, termed prosthecae. These cellular appendages, also known as ''stalks'', are neither pili nor flagella, as they are extensions of the cellular membrane and contain cytosol. One notable group of prosthecates is the genus '' Caulobacter''. Function of prostheca Prosthecates are generally chemoorganotrophic aerobes that can grow in nutrient-poor habitats, being able to survive at nutrient levels on the order of parts-per-million for which reason they are often found in aquatic habitats. These bacteria will attach to surfaces with their prosthecae, allowing a greater surface area with which to take up nutrients (and release waste products). Some prosthecates will grow in nutrient-poor soils as aerobic heterotrophs. See also Oligotroph An oligotroph is an organism that can live in an environment that offers very low levels of nutrients. They may be contrasted with copi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flagella
A flagellum (; : flagella) (Latin for 'whip' or 'scourge') is a hair-like appendage that protrudes from certain plant and animal sperm cells, from fungal spores ( zoospores), and from a wide range of microorganisms to provide motility. Many protists with flagella are known as flagellates. A microorganism may have from one to many flagella. A gram-negative bacterium '' Helicobacter pylori'', for example, uses its flagella to propel itself through the stomach to reach the mucous lining where it may colonise the epithelium and potentially cause gastritis, and ulcers – a risk factor for stomach cancer. In some swarming bacteria, the flagellum can also function as a sensory organelle, being sensitive to wetness outside the cell. Across the three domains of Bacteria, Archaea, and Eukaryota, the flagellum has a different structure, protein composition, and mechanism of propulsion but shares the same function of providing motility. The Latin word means " whip" to describe its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Denitrifying Bacteria
Denitrifying bacteria are a diverse group of bacteria that encompass many different phyla. This group of bacteria, together with denitrifying fungi and archaea, is capable of performing denitrification as part of the nitrogen cycle. Denitrification is performed by a variety of denitrifying bacteria that are widely distributed in soils and sediments and that use oxidized nitrogen compounds such as nitrate and nitrite in the absence of oxygen as a terminal electron acceptor. They metabolize nitrogenous compounds using various enzymes, including nitrate reductase (NAR), nitrite reductase (NIR), nitric oxide reductase (NOR) and nitrous oxide reductase (NOS), turning nitrogen oxides back to nitrogen gas () or nitrous oxide (). The reducing power can be supplied by organic carbon compounds (termed "heterotrophic denitrification") or inorganic substances such as hydrogen, reduced iron, or sulfur species (termed "autotrophic denitrification"). Some microbes can use either organic or inorga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Center For Biotechnology Information
The National Center for Biotechnology Information (NCBI) is part of the National Library of Medicine (NLM), a branch of the National Institutes of Health (NIH). It is approved and funded by the government of the United States. The NCBI is located in Bethesda, Maryland, and was founded in 1988 through legislation sponsored by US Congressman Claude Pepper. The NCBI houses a series of databases relevant to biotechnology and biomedicine and is an important resource for bioinformatics tools and services. Major databases include GenBank for DNA sequences and PubMed, a bibliographic database for biomedical literature. Other databases include the NCBI Epigenomics database. All these databases are available online through the Entrez search engine. NCBI was directed by David Lipman, one of the original authors of the BLAST sequence alignment program and a widely respected figure in bioinformatics. GenBank NCBI had responsibility for making available the GenBank DNA seque ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leaf Spot
A leaf spot is a limited, discoloured, diseased area of a leaf that is caused by fungal, bacterial or viral plant diseases, or by injuries from nematodes, insects, environmental factors, toxicity or herbicides. These discoloured spots or lesions often have a centre of necrosis (cell death).Horst, R. (2008). Westcott’s Plant Disease Handbook (Seventh Edition.). Springer Netherlands. Symptoms can overlap across causal agents, however differing signs and symptoms of certain pathogens can lead to the diagnosis of the type of leaf spot disease. Prolonged wet and humid conditions promote leaf spot disease and most pathogens are spread by wind, splashing rain or irrigation that carry the disease to other leaves.Lucas, G., & Campbell, L. (1992). Introduction to Plant Diseases Identification and Management (2nd ed. 1992.). Springer US. https://doi.org/10.1007/978-1-4615-7294-7 Description Leaf spots are a type of plant disease that are usually caused by pathogens and sometimes othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
