Enterococcus innesii
Classification
Domain: Bacteria; Phylum: Firmicutes; Class: Bacilli; Order: Lactobacillales; Family: Enterococcaceae.
Species
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NCBI: [uid] |
Enterococcus Innesii
Description and Significance
Enterococcus innesii is a novel species of Enterococci isolated by researchers at John Innes Centre Entomology Facility (Norwich, UK) looking at the gut microbiome of the Greater Wax Moth, Galleria mellonella. This species is significant to the medical world as it is antibiotic resistant to vancomycin, a common antibiotic taken to treat enterococci infections. By studying this new species, researchers may be able to understand the way the bacteria has mutated and better understand how to combat mutations in novel bacterium to build effective antibiotics against such resistant strains.
Genome Structure
The enterococcus innesii genome is very similar among different strains. The genome is circular in shape and, in a study on 61 different strains of the species, the following data was acquired using 16S rRNA sequencing:
- G+C Content (mol %) = 42.25 - 42.35%
- BP Count = 3692254 - 3806372 bp's
- rRNA = 15 - 22
- tRNA = 63 - 69
"E. innesii GAL7T was phylogenetically positioned among E. casseliflavus , E. flavescens (re-classified as E. casseliflavus ) and E. gallinarum cluster due to its 16S rRNA sequence similarity (99.53–99.93 %)" (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8744253/).
Cell Structure, Metabolism, and Life Cycle
- Structure
- Gram positive
- Coccoid cells
- 1.0 - 1.5 micrometer in diameter
- Commonly form chains or diplococci
- Motile
- Non-spore forming
- Colonies are non-pigmented, circular, smooth, and shiny
- Metabolism
- Facultative anaerobe
- Fermentate carbohydrates to lactic acid
- Strict fermenter (lacks Kreb's cycle)
- Negative for catalase, urease, oxidase production
- Negative for hydrolysis of hippurate and pyruvate utilization
- Positive for Voges–Proskauer reaction
- Positive for pyrrolidonyl arylamidase production and hydrolysis of aesculin and arginine dihydrolase.
- Life Cycle
- Cultures of the bacteria were capable of being grown at 10–45 °C with optimum at 30–37 °C in BHI broth
- NaCl concentrations between 0 to 8 (w/v) allowed for growth with optimum growth <6.5%
- Like other species of Enterococci, the bacteria inhabit the gastrointestinal consortia of the Greater Wax Moth, and potentially a wide variety of other host gut microbiomes.
Ecology and Pathogenesis
Enterococcus innesii are regular inhabitants of the Greater Wax Moth bowel. Enterococci are the leading cause of hospital-acquired secondary infections. Enterococcus innesii is particularly deadly due to their resistance to vancomycin, a common antibiotic used to control Enterococci infections.In particular, all strains of the bacterium encoded gene vanC-4, responsible for its phenotypic response to vancomycin. Since the bacterium is novel, it has very little data concerning its interaction with humans, but it is likely similar in virulence to its genus Enterococci. Additionally, its mechanism of circumventing the vancomycin antibiotic has yet to be determined, but the gene responsible has been determined to be the atypical gene vanC-4. The bacterium was showed to have no hemolytic activity.
References
- https://www.tgw1916.net/Enterococcus/innesii.html
- https://www.eurekalert.org/news-releases/938777
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8744253/
- https://www.news-medical.net/news/20211222/Newly-discovered-species-of-Enterococcus-bacteria-named-after-the-John-Innes-Centre.aspx
- https://microbewiki.kenyon.edu/index.php/Enterococcus#:~:text=Enterococci%20are%20Gram%2Dposistive%20cocci,a%20Kreb's%20cycle%20respiratory%20chain.
(finish up correct citation sometime)
Author
Page authored by Andrew Hall, student of Prof. Bradley Tolar at UNC Wilmington.
