Iron (II) and other heavy-metal tolerance in bacteria isolated from rock varnish in the arid region of Al-Jafer Basin, Jordan

Abstract

Abstract. Alnaimat S, Shattal SA, Althunibat O, Alsbou E, Amasha R. 2017. Iron (II) and other heavy-metal tolerance in bacteria isolated from rock varnish in the arid region of Al-Jafer Basin, Jordan. Biodiversitas 18: 1250-1257. This study deals with enumeration, identification and molecular characterization of bacterial species tolerant of iron (II) and other heavy metals that isolated from rock varnish collected from the arid region of Al-Jafer Basin, Jordan. Based on conventional culture-dependent methods, six isolates exhibited a high degree of tolerance to iron (II) and other heavy metals with a minimum inhibitory concentration (550-600 mg/L) to iron, (500-550 mg/L) to lead, (350 mg/L) to copper, (400-450 mg/L) to chromium, (150-200 mg/L) to silver, and (150-200 mg/L) to mercury, in solid media. The results showed that all isolates could tolerate 2000 mg/L Fe 2+ expressed as maximum tolerance concentration (MTC). The multiple metal resistances of these isolates were also associated with multiple antibiotic resistances. These iron tolerant isolates were shown to be capable of growth at temperatures ranging from 30 to 40°C and pH values ranging from 5 to 9 with some differences between the six isolates. On the basis of morphology and of 16S rDNA gene sequencing and phylogeny analysis, the iron-tolerant isolates were identified as Bacillus zhangzhouensis (DVCr1), Staphylococcus warneri (DVCr6), Bacillus cereus (DVCr7), Staphylococcus pasteuri (DVCu2), Brevibacterium frigoritolerans (DVPb) and Bacillus altitudinis (DVCr10). The 16S rDNA sequences from five of the six strains were submitted to GenBank and are available under the accession numbers KX781139, KX781140, KX781141, KX781145 and KX781148. The results highlight the high potential of a non-polluted habitat like rock varnish to provide new microbial communities that could be used for enhanced bioremediation of heavy metals from a contaminated site.

Heavy‐metal tolerant bacterial strains isolated from industrial sites and scrap yards in Kashmir, India

“…A previous study demonstrated that Bacillus sp. resist Fe 2+ with MIC of 550 mg/L [53]. Other researchers also reported that Bacillus megaterium is resistant to Fe at MIC of 583.33 μg/mL [36].…”

Identification of lead-resistant rhizobacteria of Carthamus tinctorius and their effects on lead absorption of Sunflower

“…In the present study, measurement of the MIC and MBC of lead nitrate on the isolated bacteria showed that the genus Brevibacterium was highly resistant to lead (MIC = MBC = 39.74 mg ml −1 ). Alnaimat demonstrated that Brevibacterium and five other bacteria exhibited a high degree of tolerance to iron (II) and other heavy metals with the minimum inhibitory concentration of 550–600 mg l −1 to iron, and 500–550 mg l −1 to lead, in solid media (Alnaimat, 2017). Also, Elahi and Rehman by determining the MIC of several types of metals including lead, found that Brevibacterium iodinum was capable for tolerating lead with the concentration of 9 mM (Elahi & Rehman, 2019).…”

The Ecology of Subaerial Biofilms in Dry and Inhospitable Terrestrial Environments

“…Overall, the results revealed taxa associated with survival under extreme conditions such as salinity (e.g., Halococcus , Kocuria , Salinimicrobium , Pontibacter , Halobacterium , Marinobacter , and Halomarina ), UV radiation (e.g., Thuepera , Deinococcus , Coccomyxa , Rubrobacter , Chroococcidiopsis , Spirosoma , Scytonema , Blastococcus , and Modestobacter ), acidic conditions (e.g., Apatococcus , Acidobacteriaceae , Beijerinciaceae and Methylocystaceae ), alkaline conditions (e.g., Spirosoma , Rubellimicrobium and Truepera ) and low water availability (e.g., Chroococcidiopsis , Knufia , Leptolyngbya , Sarcinomyces , Rubrobacter , Capnobotryella , and Scytonema ) [17,35,40,41,42]. Other genera indicated the capacity to cycle nitrogen (e.g., Thiobacillus , Malikia , Ochrobactrum , Nitrososphaera , Nitrospira , Novosphingobium , and Nitrobacter ), cycle sulfur (e.g., Thioclava , Thiobacillus , Rhodovulum , and Desulfuromonas ), autotrophically fix carbon (e.g., Chroococcidiopsis , Leptolyngbya , Nostoc , Trebouxiophyceae , Phormidium , Aurantiamonas , Thiobacillus , Thioclava , Rhodobacter , and Acidimicrobium ), utilize minerals such as iron and manganese (e.g., Aurantimonas , Acidimicrobium , and Ferrimicrobium ) and bioprecipitate minerals (e.g., Bacillus , Stenotrophomonas , Pseudomonas , and Crosiella ) [10,29,30,35,42].…”