In B.subtilis, illustrates the presence of this strategy within the rhizosphere bacterial community.Also, pSRorf encoded a putative choline sulfatase, which was accountable for the resistance phenotype observed when it was cloned independently.Choline sulfatases encoded by betC genes are necessary to convert choline sulfate into choline and are found in numerous microorganisms present in rhizospheric environments like Sinorhizobium meliloti ( ter et al).Although the betC gene is absent within the E.coli genome, we are able to assume that the presence of a gene encoding a choline sulfatase could favor the synthesis of glycine betaine from choline since in E.coli cells this final conversion is usually carried out by way of two oxidations steps catalyzed by a choline dehydrogenase (BetA) and also a glycine betaine aldehyde dehydrogenase (BetB; ter et al Sleator and Hill,).It truly is intriguing to note that only the clone carrying pSRorf accumulated much more Na than the handle, the original clone pSR and pSRorf.Furthermore, an ORF from pSR encoding a proton pumping membranebound pyrophosphatase (H PPase) was identified within this study.These proteins have already been located in all 3 domains of life and can confer resistance to cells against diverse abiotic strain including cold, drought, NaCl and metal cations, probably because the enzyme generates a membrane prospective by using PPi (Yoon et al Tsai et al).Membranebound pyrophosphatases can require Na for their activity and they will also catalyze the transport of Na outside the cell, because it has been demonstrated in the archaeal PPase from the mesophile Methanosarcina mazei and in two bacterialFrontiers in Microbiology www.frontiersin.orgOctober Volume ArticleMirete et al.Saltresistance genes revealed by metagenomicsPPases in the hyperthermophile Thermotoga maritima as well as the moderate thermophile Moorella thermoacetica (Malinen et al).More lately, an integral membrane pyrophosphatase subfamily has been described in diverse bacterial species which has the capability to transport each Na and H outdoors bacterial cells and which might have evolved from NaPPases (Luoto et al).Hence, the membranebound pyrophosphatase encoded by pSRorf, coupled with Na H antiporters PubMed ID:http://www.ncbi.nlm.nih.gov/pubmed/21509752 present in E.coli, may well be playing an important role inside the adaptation of bacterial cells to enhanced salt content (Baykov et al).A relevant finding derived from this study would be the identification of salt resistance genes related to DNA repair and to structural dynamics of nucleic acids.Examples of these genes are pSRorf and pSRorf, which encoded a DNA plus a DEADbox RNA helicase, SPI-1005 respectively.These genes had been also accountable for the NaCl resistance phenotype observed in B.subtilis.Interestingly, the environmental RNA helicase encoded by pSR showed superior adaptation to NaCl than that cloned from E.coli.DNA helicases are involved in unwinding double strand DNA and thus play crucial roles in cellular processes for example recombination, replication, transcription and repair processes whereas RNA helicases are capable of unwinding RNA duplexes and hence take part in ribosome biogenesis, transcription, translation initiation and RNA degradation (Tanner and Linder, Delagoutte and von Hippel, Kaberdin and Bl i,).In bacteria, DEADbox RNA helicases involved in cold and oxidative strain response happen to be reported inside the cyanobacterium Anabaena sp.(Yu and Owttrim,) and in Clostridium perfringens (Briolat and Reysset,), respectively.Also, upregulation of both RNA and DNA helicases trans.