Neocallimastix: Difference between revisions
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There have been no clear studies surrounding this microbe’s genome. | There have been no clear studies surrounding this microbe’s genome. | ||
Cell Structure: Neocallimastix, along with Piromyces, Orpinomyces, Anaeromyces, Caecomyces and the recently described Cyllamyces are anaerobic fungi belonging to the Chytridiomycetes family Neocallimastigacaeae . They are located in the gastrointestinal tract of large herbivorous animals, including cows and sheep. The “gut” fungi are primary colonizer s of plant material in the rumen, and together with rumen bacteria and protozoa, they are responsible for degrading of ingested plant biomass that would be otherwise indigestible to the host animal. The vast repertoire of potent plant cell-wall degrading enzymes secreted by these fungi has been characterized more fully than any other area of their biology. The structure is complex and supramolecular in order for them to degrade ingested plant cell walls. A significant number of these enzymes appear to be the result of trans-kingdom transfer from bacteria. These structures are also responsible for energy generation. . The organelle responsible for energy generation in the absence of any mitochondria, the hydrogenosome, has been used as a model to understand the metabolic processes of obligately anaerobic eukaryotes. Anaerobic fermentation products include ethanol and H2, production of the latter being associated with particular organelles termed hydrogenosomes As a result of these fungi’s extreme nature, little information is available on the genomes. The AT content of the anaerobic fungal genome is approximately 80-85 mol% and is amongst the highest reported in any organism. The nucleotide bias is reflected in both the coding and non-coding regions of the genome, with codon usage tending towards more AT-rich codons. The non-coding regions of the anaerobic fungal genome are known to be extremely AT-rich. | |||
Neocallimastix particulum xylanase NpXyn11A is an anaerobic fungus that is unusual in that it represents one of the rare examples of a fungal GH11 enzyme that is insensitive to XIP-I (wheat protein that acts on fungul but not bacterial GH11 xylanases). Neocallimastix particulum xylanase NpXyn11A displays high catalytic activity. Several conclusions have been drawn to determine the high catalytic activity. The enhanced activity of the enzyme is a result of its crystal structure of the apo form (enzyme receptor in its free state without substrates or inhibitors bound) which revealed the presence of both -3 and +3 subsites. Also, it has a pH optimum of 7.5 and a ∆G of -2.1 kcal/mol which may also contribute to enhanced activity of the enzyme. | |||
Life Cycle: | |||
The fungi of the genus Neocallimastic have a simple life-cycle alternating between a motile multi-flagellate zoospore and an extensive vegetative stage usually found associated with particulate plant material in the alimentary tract. They have been assigned to a new family, the Neocallimasticaceae, in the order Spizellomycetales of the Chytridiomycetes but their exact taxonomic affinities are uncertain. | |||
Metabolism: Evolutionarily, this genus is important because they lack one of the most important organelles involved in supplying ATP. Instead of mitochondria they have something called hydrogenosomes which also supply ATP but also produce hydrogen concurrently. Past studies have found a high probability between of hydrogenosomes and mitochondria evolving from the same organelle because they share a common ADP/ATP exchange pathway. | |||
==Ecology== | ==Ecology== | ||
Revision as of 05:13, 8 December 2008
A Microbial Biorealm page on the genus Neocallimastix
Classification
Higher Order Taxa- Eukaryota; Fungi; Neocallimastigaceae; Neocallimastix
Species- N. frontalis, N.hurleyensis, N. joyonii, N. patriciarum, N. variabilis, N. sp. AF-CTS-2G, N.sp. AF-CTS-BF-2, N. sp. GE13, N. sp. GMLF1, N. sp. JB-1999, N. sp. LM-2, N.sp. W-1
Genus: Neocallimastix
Neocallimastix is an anerobic genus of fungi. Neocallimastix forms a crucial component of the microbial population of the rumen of herbivorous mammals. Neocallimastix contains polyflagellate zoopores and grow on a range of simple and complex carbohydrates in the rumen of sheep and cattle. Neocallimastix is a type of highly fibrolytic microorganism that is capable of colonizing and degrading the major polysaccharides of plant materials (celluloseand hemicellulose) in the rumen ecosystem. This fungus could be exploited for its production of cellulolytic and xylanolytic enzymes. Neocallmstix has been shown to possess diverse plant polysaccharide hydrolase activities, a high capacity for cellulose degradation, and the ability to grow on cellulose as a sole carbohydrate source.
Genome structure
There have been no clear studies surrounding this microbe’s genome.
Cell Structure: Neocallimastix, along with Piromyces, Orpinomyces, Anaeromyces, Caecomyces and the recently described Cyllamyces are anaerobic fungi belonging to the Chytridiomycetes family Neocallimastigacaeae . They are located in the gastrointestinal tract of large herbivorous animals, including cows and sheep. The “gut” fungi are primary colonizer s of plant material in the rumen, and together with rumen bacteria and protozoa, they are responsible for degrading of ingested plant biomass that would be otherwise indigestible to the host animal. The vast repertoire of potent plant cell-wall degrading enzymes secreted by these fungi has been characterized more fully than any other area of their biology. The structure is complex and supramolecular in order for them to degrade ingested plant cell walls. A significant number of these enzymes appear to be the result of trans-kingdom transfer from bacteria. These structures are also responsible for energy generation. . The organelle responsible for energy generation in the absence of any mitochondria, the hydrogenosome, has been used as a model to understand the metabolic processes of obligately anaerobic eukaryotes. Anaerobic fermentation products include ethanol and H2, production of the latter being associated with particular organelles termed hydrogenosomes As a result of these fungi’s extreme nature, little information is available on the genomes. The AT content of the anaerobic fungal genome is approximately 80-85 mol% and is amongst the highest reported in any organism. The nucleotide bias is reflected in both the coding and non-coding regions of the genome, with codon usage tending towards more AT-rich codons. The non-coding regions of the anaerobic fungal genome are known to be extremely AT-rich.
Neocallimastix particulum xylanase NpXyn11A is an anaerobic fungus that is unusual in that it represents one of the rare examples of a fungal GH11 enzyme that is insensitive to XIP-I (wheat protein that acts on fungul but not bacterial GH11 xylanases). Neocallimastix particulum xylanase NpXyn11A displays high catalytic activity. Several conclusions have been drawn to determine the high catalytic activity. The enhanced activity of the enzyme is a result of its crystal structure of the apo form (enzyme receptor in its free state without substrates or inhibitors bound) which revealed the presence of both -3 and +3 subsites. Also, it has a pH optimum of 7.5 and a ∆G of -2.1 kcal/mol which may also contribute to enhanced activity of the enzyme.
Life Cycle: The fungi of the genus Neocallimastic have a simple life-cycle alternating between a motile multi-flagellate zoospore and an extensive vegetative stage usually found associated with particulate plant material in the alimentary tract. They have been assigned to a new family, the Neocallimasticaceae, in the order Spizellomycetales of the Chytridiomycetes but their exact taxonomic affinities are uncertain.
Metabolism: Evolutionarily, this genus is important because they lack one of the most important organelles involved in supplying ATP. Instead of mitochondria they have something called hydrogenosomes which also supply ATP but also produce hydrogen concurrently. Past studies have found a high probability between of hydrogenosomes and mitochondria evolving from the same organelle because they share a common ADP/ATP exchange pathway.
Ecology
Habitat; symbiosis; contributions to the environment.
Pathology
How does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms.
Current Research
Enter summarries of the most rescent research here--at least three required
References
Edited by student of Dr. Kirk Bartholomew
