Methanococcus voltae

A Microbial Biorealm page on the genus Methanococcus voltae

Classification

Higher order taxa

Domain: Archaea

Phylum: Euryarchaeota

Class: Methanococci

Order: Methanococcales

Family: Methanococcaceae

Genus: Methanococcus

Species

NCBI: Taxonomy

Genus species: Methanococcus voltae

Other Name: Methanococcus voltaei

Strain: Methanococcus voltae PS

Description and significance

Methanococcus voltae is a single-celled, coccoid-shaped organism that is a member of the kingdom Archaea (2) . It belongs to a specific group called methanogens, or methane producers (3). Archaea thrive under extreme environmental conditions. Methanogenic archaeobacterium occur in anaerobic environments, such as the intestinal tracts of animals, freshwater and marine sediments, and sewage. They are capable of producing methane from a limited number of substrates, including carbon dioxide and hydrogen, acetate, and methylamines: an important source of natural gas (4). M. voltae’s main pathway for energy production is through methanogenesis (5). Archaea are similar to other prokaryotes in most aspects of cell structure but are unique with respect to the lipid composition of the cytoplasmic membrane and the structure of the cell surface (6). Most archaeal species have walls made of proteins or glycoproteins, which form the outermost envelope of the cell called the surface layer (S-layer), while other species’ membranes are composed of phospholipids (7, 6). The unique cell surface of archaea requires distinct solutions to the problem of how proteins cross this barrier to be either secreted into the medium or assembled as appendages at the cell surface (6).

Genome structure

Several genes for chromatin proteins are known in Archaea. Some include histones and histone-like proteins in Euryarchaeota, as well as a DNA binding protein, Alba, which was first detected in the crenarchaeote Sulfolobus solfataricus and is thought to be involved in transcriptional regulation (8). M. voltae harbors four genes coding for all these types of chromatin proteins (8). M. voltae’s genomic structure and adaptations provide insight into understanding the organism’s interactions with its extreme habitat. “Methanococcus voltae (strain PS) is known to produce a filterable, DNase-resistant agent (called VTA, for voltae transfer agent), which carries very small fragments (4400 bp) of bacterial DNA and is able to transduce bacterial genes between derivatives of the strain” (9). M. voltae was found to have a system of gene transfer similar to general transduction except that the bacteriophage component (in terms of virus replication) is defective or absent (9). VTA is responsible for the transfer and its 4.4kb fragments of DNA are resistant to DNase.

Cell structure and metabolism

Describe any interesting features and/or cell structures; how it gains energy; what important molecules it produces.

Ecology

Describe any interactions with other organisms (included eukaryotes), contributions to the environment, effect on environment, etc.

Pathology

How does this organism cause disease? Human, animal, plant hosts? Virulence factors, as well as patient symptoms.

Application to Biotechnology

Does this organism produce any useful compounds or enzymes? What are they and how are they used?

Current Research

Enter summaries of the most recent research here--at least three required

References

[Sample reference] Takai, K., Sugai, A., Itoh, T., and Horikoshi, K. "Palaeococcus ferrophilus gen. nov., sp. nov., a barophilic, hyperthermophilic archaeon from a deep-sea hydrothermal vent chimney". International Journal of Systematic and Evolutionary Microbiology. 2000. Volume 50. p. 489-500.

(1) "Methanococcus voltae". NCBI Taxonomy Browser. 27 August 2007. [1]

(2) Bayley, DP. & Jarrell (1999) Overexpression of Methanococcus voltae Flagellin Subunits in Escherichia coli and Pseudomonas aeruginosa: a Source of Archaeal Preflagellin. American Society for Microbiology, 181(14): 4146–4153. Link to Article

(3) Tumbula, D., and Whitman. W., “Genetics of Methanococcus: possibilities for functional genomics in Archaea.” Molecular Microbiology 1999. Volume 33: 1-7.

(4) "Methanococcus voltae" Dictionary Reference. 27 Aug 2007. Link to Website

(5) Zhu W, Reich CI, Olsen GJ, Giometti CS, Yates JR 3rd., J. Proteome Res. 2004. Volume 3: 538-548.

(6) Albers, SV. (2006). Protein secretion in the Archaea: multiple paths towards a unique cell surface. Nature reviews. Microbiology, 4(7), 537-547. Link to Article

(7) Sleytr, UB., Egelseer, E., Ilk, N., Pum, D., and Schuster, B., “S-Layers as a basic building block in a molecular construction kit.” 2007. Volume 274(2): 323-334.

(8) Heinicke, I. (2004). Mutational analysis of genes encoding chromatin proteins in the archaeon Methanococcus voltae indicates their involvement in the regulation of gene expression. Molecular genetics and genomics, 272(1), 76-87. Link to Article

(9) Ng, SYM, & Ng. (2007). Archaeal signal peptidases. Microbiology, 153(2), 305-314. Link to Article

(10) Lang, AS, & LANG. (2007). Importance of widespread gene transfer agent genes in alpha-proteobacteria. Trends in Microbiology, 15(2), 54-62. Link to Article

(11) "Methanococcus voltae" 27 Aug 2007. Link to Website

(12) Niess, UM. (2004). Dimethylselenide demethylation is an adaptive response to selenium deprivation in the archaeon Methanococcus voltae. Journal of bacteriology, 186(11), 3640-3648. Link to Article

(13) Dawes, Edwin. Microbial Energetics. New York: Blackie. 1986

(14) Reeve, J.N. “Molecular biology of Methanogens.” Annu Rev Microbiol. 1992. Volume 46: 165–191.

(15) Allers, T. (2005). Archaeal genetics - The third way. Nature reviews. Genetics, 6(1), 58-73. Link to Article

(16) "Methanococcus voltae" Genamics GenomeSeek. 27 Aug 2007. Link to Website

Edited by student of Rachel Larsen