Vibrio natriegens


Vibrio natriegens is a Gram-negative marine bacterium. It was first isolated from salt marsh mud. It is a salt-loving organism requiring about for growth. It reacts well to the presence of sodium ions, which appear to stimulate growth in Vibrio species, to stabilise the cell membrane, and to affect sodium-dependent transport and mobility. Under optimum conditions, and all nutrients provided, the doubling time of V. natriegens can be less than 10 minutes. V. natriegens can live successfully and rapidly divide in its coastal areas due to its large range of metabolic fuel. Recent research has displayed that Vibrio natriegens has a flexible metabolism, which allows it to consume a large variety of carbon substrates, reduce nitrates, and even fix nitrogen from the atmosphere under nitrogen-limiting and anaerobic conditions. In the laboratory, the growth medium can be easily changed, thus affecting the growth rate of a culture. V. natriegens is commonly found in estuarine mud.

Aquaculture and antibiotic resistance

Many strains of Vibrio, including natriegens, are pathogenic against farmed aquacultures such as the abalone and have recently destroyed farmed abalones when aquacultures get infected. In response, fishers have taken to inoculating tanks with large amounts of antibiotics, which has resulted in Vibrio natriegens developing a potent antibiotic resistance to many drugs. In a recent study, the AbY-1805 strain of Vibrio natriegens was shown to be completely resistant against 17 of the 32 tested antibiotics and at least partially resistant against 22 of the 32.

Biochemical characteristics of ''V. natriegens''

Colony, morphological, physiological, and biochemical characteristics of Vibrio natriegens are shown in the Table below.
Test typeTestCharacteristics
Colony charactersSizeMedium
Colony charactersTypeRound
Colony charactersColorWhitish
Colony charactersShapeConvex
Morphological charactersShapeVibrio
Physiological charactersMotility+
Physiological charactersGrowth at 6.5% NaCl+
Biochemical charactersGram's staining–
Biochemical charactersOxidase+
Biochemical charactersCatalase+
Biochemical charactersOxidative-FermentativeOxidative
Biochemical charactersMotility+
Biochemical charactersMethyl red–
Biochemical charactersVoges-Proskauer–
Biochemical charactersIndole–
Biochemical charactersH2S Production+
Biochemical charactersUrease+
Biochemical charactersNitrate reductase+
Biochemical charactersβ-Galactosidase+
Hydrolysis ofGelatin+
Hydrolysis ofAesculin+
Hydrolysis ofCasein+
Hydrolysis ofTween 40+
Hydrolysis ofTween 60+
Hydrolysis ofTween 80+
Acid production fromGlycerol+
Acid production fromGalactose+
Acid production fromD-Glucose+
Acid production fromD-FructoseV
Acid production fromD-MannoseV
Acid production fromMannitolV
Acid production fromN-Acetylglucosamine+
Acid production fromAmygdalin–
Acid production fromMaltose+
Acid production fromD-Melibiose–
Acid production fromD-Trehalose–
Acid production fromGlycogen+
Acid production fromD-Turanose+

Note: + = Positive, – =Negative, V =Variable

Biotechnological uses

Owing to its rapid growth rate, ability to grow on inexpensive carbon sources, and capacity to secrete proteins into the growth media, efforts are underway to leverage this species as a host for molecular biology and biotechnology applications. Recently, V. natriegens crude extract has been shown by multiple research groups to be a promising platform for cell-free expression. Scientists are also hoping that Vibrio natriegens, with its incredible growth speed, will make microbial experiments in outer space, where time is an extremely valuable asset, much quicker. Interestingly, it has been shown that Vibrio natriegens might grow even faster in space despite its incredibly quick doubling speed on Earth. An experiment displayed that after 24 hours of growth the Vibrio cells grown in zero gravity were 60 times denser than those grown in full gravity, possibly attributable to an extended exponential growth phase in low-gravity conditions.