Genetic fingerprint and diversity evaluation of halophilic Bacillus species by RAPD-PCR.

Ingrid Georgina Orce,Verónica Patricia Irazusta,Verónica Beatriz Rajal,María Julia Torres,Mónica Aparicio,Fabiana Lilian Martínez

doi:10.1590/0001-3765202120191430

Abstract

Random amplified polymorphic DNA-PCR (RAPD-PCR) is a technique successfully used to generate characteristic fingerprints of different bacteria. Bacillus is a genus that includes heterogeneous species, thus a combination of different techniques is essential for their identification. Here we used RAPD-PCR methodology to distinguish among genetically similar strains and to evaluate the genetic diversity of Bacillus species from the Salar del Hombre Muerto, in the Northwest of Argentina. The RAPD-PCR used allowed obtaining different amplification profiles for each Bacillus species and strains. By comparing the fingerprint profiles, we could observe that some of the salt flat isolates showed similar profiles than identified strains. As expected, the bacilli group isolated revealed a wide heterogeneity. RAPD-PCR was found to be a quick and reliable technique to evaluate the diversity of Bacillus strain and was successfully applied to characterize the genetic diversity present in the Salar del Hombre Muerto.

Highlights

The Salar del Hombre Muerto is in the province of Catamarca, northwest of Argentina
Despite the accumulated salts, which limit nutrient absorption and reduce water availability, some microorganisms known as halophiles, can inhabit and grow under this condition (Ma et al 2010)
Despite all the efforts invested, some microorganisms are indistinguishable even using those sequencing methodologies. This is true for bacteria from Bacillus, a large and heterogeneous genus including many species, where combinations of different techniques are essential for their identification (Kim & Park 2009)

Summary

Introduction

The Salar del Hombre Muerto is in the province of Catamarca, northwest of Argentina It is a typical high-altitude salt flat in which rising groundwater is a saturated brine that forms salt deposits when the water is evaporated (Martínez et al 2019). Despite the accumulated salts, which limit nutrient absorption and reduce water availability, some microorganisms known as halophiles, can inhabit and grow under this condition (Ma et al 2010). As these microorganisms have in general extraordinary activities, they have become the search engine of many work teams (Ma et al 2010, Sahay et al 2012, Gupta et al 2016)

Objectives

Methods

Results