Elusimicrobium minutum
Encyclopedia
Elusimicrobium minutum is an ultramicrobacterium
and first accepted member to be cultured of a major bacterial lineage
previously known only as candidate phylum Termite Gut 1 (TG1), which has accordingly been renamed phylum Elusimicrobia
.
It was isolated in the laboratory of Andreas Brune at the Max Planck Institute for Terrestrial Microbiology
, from the scarab beetle. It is a mesophilic, obligately anaerobic ultramicrobacterium with a gram-negative
cell envelope
.
Cells are typically rod shaped, but cultures are pleomorphic in all growth phases (0.3 to 2.5 μm long and 0.17 to 0.3 μm wide). The isolate grows heterotrophically on sugars and ferments D-galactose, D-glucose, D-fructose, D-glucosamine, and N-acetyl-D-glucosamine to acetate, ethanol, hydrogen, and alanine as major products but only if amino acids are present in the medium
, and an unusual peptide degradation pathway comprising transamination reactions. It also reveals the presence of genes coding for peptidoglycan
and lipopolysaccharide
biosynthesis. The genome also seems to encode 60 PilE genes putatively involved in pilus assembly, polyketide synthesis, non-ribosomal peptide synthesis and many other still undiscovered metabolic traits .
Ultramicrobacteria
Ultramicrobacteria are bacteria that are considerably smaller than normal bacterial cells and are 0.3 to 0.2 micrometres in diameter. This term was first used in 1981, to refer to cocci in seawater that were less than 0.3 μm in diameter. These cells have also been recovered from soil and appeared...
and first accepted member to be cultured of a major bacterial lineage
Bacterial phyla
The bacterial phyla are the major lineages of the domain Bacteria.In the scientific classification established by Carl von Linné, each bacterial strain has to be assigned to a species , which is a lower level of a hierarchy of ranks...
previously known only as candidate phylum Termite Gut 1 (TG1), which has accordingly been renamed phylum Elusimicrobia
Elusimicrobia
The phylum Elusimicrobia previosuly known as 'Termite Group 1' has been shown to be widespread in different ecosystems like marine environment, sewage sludge, contaminated sites and soils...
.
It was isolated in the laboratory of Andreas Brune at the Max Planck Institute for Terrestrial Microbiology
Max Planck Institute for Terrestrial Microbiology
The Max Planck Institute for Terrestrial Microbiology is a research institute for microbiology in Marburg, Germany. It was founded in 1991 and is one of 80 institutes in the Max Planck Society ....
, from the scarab beetle. It is a mesophilic, obligately anaerobic ultramicrobacterium with a gram-negative
Gram-negative
Gram-negative bacteria are bacteria that do not retain crystal violet dye in the Gram staining protocol. In a Gram stain test, a counterstain is added after the crystal violet, coloring all Gram-negative bacteria with a red or pink color...
cell envelope
Cell envelope
The cell envelope is the cell membrane and cell wall plus an outer membrane, if one is present.Most bacterial cell envelopes fall into two major categories: Gram positive and Gram negative. These are differentiated by their Gram staining characteristics....
.
Cells are typically rod shaped, but cultures are pleomorphic in all growth phases (0.3 to 2.5 μm long and 0.17 to 0.3 μm wide). The isolate grows heterotrophically on sugars and ferments D-galactose, D-glucose, D-fructose, D-glucosamine, and N-acetyl-D-glucosamine to acetate, ethanol, hydrogen, and alanine as major products but only if amino acids are present in the medium
The Genome of Elusimicrobium minutum
The 1.64 Mbp genome of E. minutum reveals the presences of several genes required for uptake and fermentation of sugars via the Embden-Meyerhof pathway, including several hydrogenasesHydrogenase
A hydrogenase is an enzyme that catalyses the reversible oxidation of molecular hydrogen . Hydrogenases play a vital role in anaerobic metabolism....
, and an unusual peptide degradation pathway comprising transamination reactions. It also reveals the presence of genes coding for peptidoglycan
Peptidoglycan
Peptidoglycan, also known as murein, is a polymer consisting of sugars and amino acids that forms a mesh-like layer outside the plasma membrane of bacteria , forming the cell wall. The sugar component consists of alternating residues of β- linked N-acetylglucosamine and N-acetylmuramic acid...
and lipopolysaccharide
Lipopolysaccharide
Lipopolysaccharides , also known as lipoglycans, are large molecules consisting of a lipid and a polysaccharide joined by a covalent bond; they are found in the outer membrane of Gram-negative bacteria, act as endotoxins and elicit strong immune responses in animals.-Functions:LPS is the major...
biosynthesis. The genome also seems to encode 60 PilE genes putatively involved in pilus assembly, polyketide synthesis, non-ribosomal peptide synthesis and many other still undiscovered metabolic traits .