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Original citation: Selama, Okba, Amos, Gregory C. A., Djenane, Zahia, Borsetto, Chiara, Laidi, Rabah Forar, Porter, David, Nateche, Farida, Wellington, E. M. H. (Elizabeth M. H.), 1954- and Hacène, Hocine. (2014) Screening for genes coding for putative antitumor compounds, antimicrobial and enzymatic activities from haloalkalitolerant and haloalkaliphilic bacteria strains of Algerian Sahara soils. BioMed Research International, 2014 . Article number 317524. Permanent WRAP url: http://wrap.warwick.ac.uk/61907 Copyright and reuse: The Warwick Research Archive Portal (WRAP) makes this work of researchers of the University of Warwick available open access under the following conditions. This article is made available under the Creative Commons Attribution- 3.0 Unported (CC BY 3.0) license and may be reused according to the conditions of the license. For more details see http://creativecommons.org/licenses/by/3.0/ A note on versions: The version presented in WRAP is the published version, or, version of record, and may be cited as it appears here. For more information, please contact the WRAP Team at: [email protected] http://wrap.warwick.ac.uk/ Hindawi Publishing Corporation BioMed Research International Volume 2014, Article ID 317524, 11 pages http://dx.doi.org/10.1155/2014/317524 Research Article Screening for Genes Coding for Putative Antitumor Compounds, Antimicrobial and Enzymatic Activities from Haloalkalitolerant and Haloalkaliphilic Bacteria Strains of Algerian Sahara Soils Okba Selama,1 GregoryC.A.Amos,2 Zahia Djenane,1 Chiara Borsetto,2 Rabah Forar Laidi,3 David Porter,2 Farida Nateche,1 ElizabethM.H.Wellington,2 and Hocine Hacène1 1 Microbiology Group, Laboratory of Cellular and Molecular Biology, Faculty of Biological Sciences, USTHB, BP 32, EL ALIA, BabEzzouar,Algiers,Algeria 2 School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK 3 Department de Biologie, Ecole Normale Superieure (ENS), Vieux Kouba, Alger, Algeria Correspondence should be addressed to Hocine Hacene;` h [email protected] Received 26 February 2014; Revised 13 April 2014; Accepted 6 May 2014; Published 27 May 2014 Academic Editor: Ameur Cherif Copyright © 2014 Okba Selama et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Extreme environments may often contain unusual bacterial groups whose physiology is distinct from those of normal environments. To satisfy the need for new bioactive pharmaceuticals compounds and enzymes, we report here the isolation of novel bacteria from an extreme environment. Thirteen selected haloalkalitolerant and haloalkaliphilic bacteria were isolated from Algerian Sahara Desert soils. These isolates were screened for the presence of genes coding for putative antitumor compounds using PCR based methods. Enzymatic, antibacterial, and antifungal activities were determined by using cultural dependant methods. Several of these isolates are typical of desert and alkaline saline soils, but, in addition, we report for the first time the presence of a potential new member of the genus Nocardia with particular activity against the yeast Saccharomyces cerevisiae. In addition to their haloalkali character, the presence of genes coding for putative antitumor compounds, combined with the antimicrobial activity against a broad range of indicator strains and their enzymatic potential, makes them suitable for biotechnology applications. 1. Introduction another niche harbouring “extremophiles” [8]; major catego- ries of extremophiles include halophiles, thermophiles, aci- There is an increasingly urgent need for new active biomole- dophiles, alkaliphiles, and haloalkaliphiles [6, 9]. cules and enzymes for use in industry and therapy [1]. The haloalkaliphiles bacteria have attracted a great deal of However, the rate of discovery of new useful compounds has attention from researchers in this last decade [9]. In 1982, the been in decline [2, 3] and because of this there is an interest in term haloalkaliphile was used for the first time to describe investigating previously unexplored ecological niches [4, 5], bacteria that are both halophilic and alkaliphilic [10]. This particularly extreme environments. These environments have group of bacteria is able to grow optimally or very well at pH provided a useful source of novel biologically active com- values at or above 10 along with high salinity (up to 25% (w/v) pounds in recent years [1, 6, 7]. NaCl) [11]. Extreme environments are distributed worldwide. These To encounter such harsh conditions, haloalkaliphilic ecosystems were thought to be lifeless as insurmountable microorganisms have found various physiological strategies extreme physical and chemical barriers to life exhibit. With to sustain their cell structure and function [12, 13]. These the advancement of our knowledge, we now see them as yet bacteria have widely been identified and studied from the 2 BioMed Research International hypersaline environments, soda lakes, solar saltern, salt Spain brines, carbonate springs, and Dead Sea [14]. Their survival Mediterranean Sea obviously indicated the widespread distribution of such organisms in natural saline environments [12, 15]. Atlantic The interest in haloalkaliphilic microorganisms is due not Ocean only to the necessity for understanding the mechanisms of adaptation to multiple stresses and detecting their diversity, Biskra Morocco Djelfa Tunisia but also to their possible application in biotechnology [9]. The present work involved the isolation and character- ization of new haloalkalitolerant and haloalkaliphilic bac- Bechar teria able to produce extremozymes and elaborate natural Ouargla bioactive compounds effective against pathogenic bacteria Algerian Sahara Libya and fungi as well. The screening for genes coding for putative antitumor compounds by PCR with three sets of primers Adrar In Salah wasalsoperformed.Wehavebeeninterestedinsoilsof Algerian Sahara Desert, which is one of the biggest deserts and encompasses one of the most extreme environments worldwide (Sabkha and Chott). However, it is also considered to be one of the less explored parts. Our team has been N Tamanrasset interested in these magnificent ecosystems for many years Mauritania and the few studies that have been published have shown Niger great active biomolecules [16–18], biodiversity of interesting 300 Mali new taxa [19–24], and enzymes [25, 26]. (km) Figure 1: Location of the sampled sites from Algerian Sahara Desert. ∘ ∘ ∘ ∘ Djelfa: 35 16 47.5 N343 25.4 E; Biskra: 34 11 01.1 N607 21.8 E; ∘ ∘ ∘ 2. Material and Methods Ouargla: 33 29 28.85 N 5 59 10.52 E; Tamanrasset 23 00 30.01 N ∘ ∘ ∘ 5 13 33.32 E; In Salah: 27 11 31.60 N227 12.52 E; Adrar: ∘ ∘ ∘ ∘ 2.1. Sampling and Strains Isolation. Samples from different 27 44 48.14 N016 10.21 W; Bechar: 30 51 25.71 N159 58.56 soils(7sites)ofAlgeria’sSaharaDesertwerecollectedon W. March2010(100–300gpersiteinsterilebags)(Figure 1). Most samples were saline and alkaline soils, with an electrical ∘ conductivity between 1.4 and 20.2 mS/cm (at 20 C) and pH 2.3. Molecular Study ∘ range of 7.5–9; the temperature varies from 22 Cnorthto ∘ 44 C south of the Sahara. One gram from each sample was 2.3.1. DNA Extraction. Total genomic DNA from the differ- suspended in 9 ml sterile water (of 0.9%, 10%, and 20% NaCl ent selected bacteria for this study was isolated and purified −4 w/v) and serial dilutions to 10 . For each dilution and for using Qiagen Blood and Tissue DNA extraction kit (Qiagen, each concentration, soil particles were allowed to sediment; UK). DNA was eluted in Tris-HCL and its quantity and qual- ity were tested using NanoDrop 2000 (Thermo Scientific). then 0.1 mL of the liquid phase was spread onto the surface ∘ of each of the modified International Streptomyces Project 2 DNA was stored at −20 Cuntiluse. (ISP2) [27] media agar supplemented with NaCl with respect to the various concentrations of salt used for dilutions (0.9%, 2.3.2. Molecular Identification. The amplification of 16S 10%, and 20% NaCl w/v) and adjusted to either pH= 7 or rRNA gene for the selected strains was performed using pH=10byadding5MNaOHbeforeautoclavingandspread the universal bacterial primer pairs pA/pH designed by onto nutrient agar plates. The plates were maintained at Edwards et al. [28](Table 1). PCR reactions were performed ∘ ∘ constanthumidityincubatedateither30Cor50Cfor15 in final reaction volume of 50 L containing 1 L(10–100ng) days. Colonies were picked out and repeatedly restreaked of DNA template, 25 L master mix (Promega, Madison, until purity was confirmed. All bacterial culture isolates were WI, USA), 1 L(10M) of each primer, and 1 LofBSA ∘ stored at 4 C in the same medium used for isolation. (10 mg/mL) (Promega, Madison, WI, USA). PCR products were analyzed on 1.5% (w/v) agarose (Sigma, UK) in 40 mM Tris-acetate with 1 mM EDTA (TAE) buffer at pH of 8.0 −1 2.2. Physiological Growth Parameters. Physiological growth stained with ethidium bromide at 0.5 gmL .Bandsof parameters for the thirteen selected strains were determined the corresponding size were cut out and purified with by agar plate method on modified ISP2 medium depending gel extraction kit (Qiagen; Venlo, Netherlands) as per the on the modified parameter. Salinity tolerance was examined manufacturer’s instructions. for0,1,5,10,15,20,and25%NaClw/v.ThepHgrowthrange The nucleotide sequences for the 16S rRNA

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