The Ecological Coherence of Temperature and Salinity Tolerance Interaction and Pigmentation in a Non-marine Vibrio Isolated from Salar de Atacama

Abstract

The occurrence of microorganisms from the Vibrio genus in saline lakes from northern Chile had been evidenced using Numerical Taxonomy decades before and, more recently, by phylogenetic analyses of environmental samples and isolates. Most of the knowledge about this genus came from marine isolates and showed temperature and salinity to be integral agents in shaping the niche of the Vibrio populations. The stress tolerance phenotypes of Vibrio sp. Teb5a1 isolated from Salar de Atacama was investigated. It was able to grow without NaCl and tolerated up to 100 g/L of the salt. Furthermore, it grew between 17° and 49°C (optimum 30°C) in the absence of NaCl, and the range was expanded into cold temperature (4–49°C) in the presence of the salt. Other additional adaptive strategies were observed in response to the osmotic stress: pigment production, identified as the known antibacterial prodigiosin, swimming and swarming motility and synthesis of a polar flagellum. It is possible to infer that environmental congruence might explain the cellular phenotypes observed in Vibrio sp. considering that coupling between temperature and salinity tolerance, the production of antibacterial agents at higher temperatures, flagellation and motility increase the chance of Vibrio sp. to survive in salty environments with high daily temperature swings and UV radiation.

Characterization and Salt Response in Recurrent Halotolerant Exiguobacterium sp. SH31 Isolated From Sediments of Salar de Huasco, Chilean Altiplano

“…Moreover, cells grown in the absence of chloride were lacking flagella; however, it was restored upon the addition of chloride ( Roeßler et al, 2000 ). A recent report indicates that the salt concentration is dependent on motility in a pigment halotolerant Vibrio strain isolated from Salar de Atacama, but motility was inhibited in higher salt concentrations (150 g/l NaCl; Gallardo et al, 2016 ). Substantial energy is needed for flagellar biosynthesis and bacteria are able to inhibit certain processes in response to stress, motility was reduced, and biofilm formation was seen in SH31 ( Figure 4 ) a general bacterial response to osmotic stress found in diverse organisms, as it was shown in Pseudomonas putida ( Bojanovič et al, 2017 ).…”

“…The effect of several stress factors were studied in an Enterobacter strain isolated from a high-altitude Andean saline lake ( Dib et al, 2008 ). One member of the Vibrio genus, Vibrio ruber , is one the most studied halophilic eubacteria ( Ventosa et al, 1998 ), and members of this genus have also been found in non-marine systems such as Salar de Atacama, where the relation between pigmentation and salt tolerance was investigated ( Gallardo et al, 2016 ).…”

The Microbiome of Neotropical Water Striders and Its Potential Role in Codiversification

“…Unfortunately, our small sample size prevented us from determining if this pattern is consistent across species or if some bacterial taxa show a stronger contribution to microbiome diversity than others. Microbiome composition could also be influenced by habitat type [65][66][67][68][69][70], particularly because we sampled one fresh and two brackish-water sites. Indeed, we found significant differences in the number of ASVs across sites, with brackish-water sites showing the highest number of unique bacterial taxa.…”

Biosynthesis and Bioactivity of Prodiginine Analogs in Marine Bacteria, Pseudoalteromonas: A Mini Review

“…Due to the diversity among prodiginine-producing bacteria, it is difficult to determine the precise biological and ecological role of the pigment. Based on previous studies, it can be inferred that prodiginine may provide a mode of defense against competing microorganisms or a potential response to environmental stressors (Gallardo et al, 2016).…”