Thermophilic bacteria in Moroccan hot springs, salt marshes and desert soils

Abstract

The diversity of thermophilic bacteria was investigated in four hot springs, three salt marshes and 12 desert sites in Morocco. Two hundred and forty (240) thermophilic bacteria were recovered, identified and characterized. All isolates were Gram positive, rod-shaped, spore forming and halotolerant. Based on BOXA1R-PCR and 16S rRNA gene sequencing, the recovered isolates were dominated by the genus Bacillus (97.5%) represented by B. licheniformis (119), B. aerius (44), B. sonorensis (33), B. subtilis (subsp. spizizenii (2) and subsp. inaquosurum (6)), B. amyloliquefaciens (subsp. amyloliquefaciens (4) and subsp. plantarum (4)), B. tequilensis (3), B. pumilus (3) and Bacillus sp. (19). Only six isolates (2.5%) belonged to the genus Aeribacillus represented by A. pallidus (4) and Aeribacillus sp. (2). In this study, B. aerius and B. tequilensis are described for the first time as thermophilic bacteria. Moreover, 71.25%, 50.41% and 5.41% of total strains exhibited high amylolytic, proteolytic or cellulolytic activity respectively.

Thermotolerant bacteria of biotechnological potential from hot springs in Eritrea

“…Relatively higher cfu counts were retrieved from Elegedi, a boiling hot spring than the other hot springs. The total counts in this study were higher than 50-5000 cfu/ml recorded in Morrocan hot springs (Aanniz et al, 2015) and 170-1330 cfu/ml recorded in the geothermal springs in Saudi Arabia (Khiyami et al, 2012). The sequences for 24 isolates were without ambiguities.…”

“…They were observed to be the predominant groups isolated from hot springs in Indonesia using other enrichment medium such as spring water enriched with nutrient broth (Yohandini, 2015). Bacillus have also been isolated using nutrient broth supplemented with 1% Tween or Olive oil from geothermal springs in Armenia (Shahinyan et al, 2015), Castenholz TYE medium from hot springs in India (Verma et al, 2014), Tryptone Soy Agar (TSY) from hot springs in Morocco (Aanniz et al, 2015) and nutrient agar from hot springs in Fiji (Narayan et al, 2008). The genus Bacillus and related genera are reported to be widely distributed in nature.…”

Identifying the microbial taxa that consistently respond to soil warming across time and space

“…First, most of the bacterial taxa found in soil remain understudied (Ramirez et al ., ), with their specific responses to temperature unknown. Although there has been extensive research on thermophilic and psychrophilic bacteria (e.g., Bottos et al ., ; Siddiqui et al ., ; Aanniz et al ., ), these taxa are not likely to be abundant in most soils and the temperature optima that define thermophiles and psychrophiles (40 °C to 70 °C and −20 °C to 10 °C, respectively) are either outside or overlap minimally with the range of temperatures experienced by many soils. Thus, knowing what taxa are thermophilic or psychrophilic is unlikely to be useful for predicting how microbial communities in most soils will respond to anticipated mean increases in global surface temperatures of 2–4 °C by the year 2100 (IPCC, ).…”

Morphological, enzymatic screening, and phylogenetic analysis of thermophilic bacilli isolated from five hot springs of Myagdi, Nepal

“…Thermophiles can grow at higher temperatures (55-80°C) as they possess physically and chemically stable enzymes showing high metabolism also at the higher temperature. Their study has become a major domain of research due to their potential to produce industrially interesting thermostable enzymes (proteases, amylases, lipases, xylanases, and DNA polymerases) and exopolysaccharides that function under extreme conditions [3]. Thermophilic organisms grow in a limited number of sites, and exploration of such microorganisms from geothermal environments has not only provided greater insights into the origin and evolution of earliest life but also has provided access to significant bioresources with potential applications in food and biotechnology industry [4].…”