The histone-like protein HU is the most-abundant DNA-binding protein in bacteria.The HU protein non-specifically binds and bends DNA as a hetero- or homodimer, and can participate in DNA supercoiling and DNA condensation. It also takes part in DNA functions such as replication, recombination, and repair. HU does not recognize any specific sequences but shows a certain degree of specificity to cruciform DNA and repair intermediates such as nick, gap, bulge, etc. To understand the features of HU binding to DNA and repair intermediates, a fast and easy HU protein purification method is required. Here we report a two-step purification procedure of HU from Halobacillus karajensis (the gram positive and moderately halophilic bacteria isolated from Karaj surface soil). The method of HU purification allows obtaining a pure nontagged protein. Salting out and ion exchange chromatography were applied for purification, and the purified protein was identified by immunoblotting. Results showed that the molecular weight of the purified protein was approximately 11 kDa which is immunologically similar to the Bacillus subtilis HU protein (HBsu).

Heavy metals are generally discharged from untreated wastewater in the aquatic ecosystem. This study was aimed to investigating the effective parameters in the sorption of nickel metal by a native halophile bacterium isolated from sediments of the Miankaleh Wetland in the north of Iran. Halobacillus sp. KN57 as the most resistant Gram-positive strain was selected and identified by phenotypic and phylogenetic properties (16S rRNA). The optimum contact time, pH, temperature, salinity, and initial biosorbent concentration of nickel for this strain were 100 min, 7, 30° C, 10%, 1 g. L-1, and 150 mg. L-1, respectively. The nickel biosorption was 111. 11 mg/g by the selected strain under the laboratory conditions, followed Langmuir isotherm with a correlation coefficient of more than 0. 98 and the maximum single layer sorption. In addition, the kinetics of nickel biosorption of this strain correspond to a pseudo second order kinetic model with a correlation coefficient of more than 0. 99. Scanning electron microscopy was applied to confirm the biosorption of Ni2+ by Halobacillus sp. KN57. Finally, the FT-IR spectrum identified that the amide, carbonyl, and amine functional groups were participated in binding to nickel ions. The results showed that the native bacterial strain (Halobacillus sp. KN57) isolated from Miankaleh Wetland, is potentially a promising biosorbent for sorption of nickel metal.

Lipases are particularly important because they specifically hydrolyze acyl glycerol, oils, which are of great interest for different industrial applications. Some halophilic microorganisms produced some lipases. Halophilic bacteria have greater ability to produce salt and thermo tolerant enzymes like amylases, proteases and lipases. Most industrial enzymatic functions may be stopped by concentrated salt solutions and high temperatures; therefore, halophilic enzymes that have optimal activity at a vast range of temperature, pH and ionic strength, would be considered as suitable biocatalysts in industrial processes. The aim of this study was to isolate and study the halophilic lipase producing bacteria from the Miankaleh Wetland. The lipase activity was measured using titrimetric methods. Three halophilic strains (AR11, AR18 and AR28) were isolated from the Miankaleh wetland and were screened for the production of hydrolytic enzymes and lipolytic activity. Among three isolates, one strain was selected for identification using the molecular methods and some morphological characteristics. The bacterium Halobacillus truperi AR11 with 1. 82 ± 0. 1 U/mL lipase activity was selected as the highest lipase producing isolate. Lipase enzyme produced by this potential isolate was also characterized for determining its optimal activity. Effect of different pH, NaCl concentration and temperature on lipase activity was determined. The optimum pH for AR11 was found to be 9, while the optimum temperature and NaCl concentration for lipase activity was found to be 45º C and 5 % NaCl, respectively. This is the first report of isolation and molecular identification of lipase producing halophilic bacteria from the Miankaleh wetland.

L-DOPA (L-3, 4-dihydroxyphenylalanine) was first discovered in the 1960s as the most effective treatment for Parkinson's disease. In the present research, for the first time, isolation and identification of L-tyrosine-degrading moderately halophilic bacteria and evaluation their ability as biocatalyst for the bioconversion of L-tyrosine into L-dopa was studied. Using an enrichment technique in tyrosine-containing medium, the Ltyrosine-degrading strain SL-7 with the highest ability to bioconvert L-tyrosine into Ldopa was phenotypically and molecularly characterized and its 16S rDNA sequence was submitted as Halobacillus sp. SL-7. In order to increase the reaction efficiency and prevent the degradation of the metabolites (L-dopa), One-factor-at-a-time optimization method was used to improve the yield of L-dopa in the conversion reaction under resting cells of Halobacillus sp. SL-7. Based on our results, the optimum bioconversion conditions for the production of L-dopa can be summarized as follows: initial tyrosine concentration 1. 5 g/l, biomass concentration 7. 5 g/l, copper concentration 0. 03 g/l and peptone at the concentration 1 g/l as cosubstrate. Under these conditions, the maximal L-dopa concentration (0. 75 g/l with a molar yield of 46. 2%) was achieved after a 36 h reaction. This is the first report on the potential of resting cells of Halobacillus sp. SL-7, A moderately halophilic bacterium with ability biological converting L-tyrosine into Ldopa.

Background and Objectives: : The Caspian Sea is affected by many pollutants, including toxic and heavy metals, which enter the sea through rivers contaminated with urban and industrial wastewater. Heavy metal contamination in wastewater is a significant concern for human health and the environment, prompting increased efforts to develop efficient and sustainable removal methods. Despite significant efforts in the last few decades, further research initiatives remain vital to comprehensively address the long-term performance and practical scalability of various adsorption methods and adsorbents for heavy metal biosorption Methods: In this study, Halobacillus trueperi bacteria isolated from the waste paint factory Babol were studied molecularly from the perspective of biochemistry. The effects of parameters such as pH, temperature, concentration of metal-on-metal ions, and removal efficiency of nickel and cadmium were investigated. Using the techniques of Fourier transform infrared (FT-IR) and scanning electron microscopy (SEM), effective bio-absorption was analyzed.  Findings: The highest adsorption rate of cadmium and nickel metal ions was observed by bacteria studied at pH of about 6 and 7, respectively, so that higher pH was observed due to metal ion deposition, and lower pH due to reduced adsorption competition. The best temperature for adsorption in both metals was about 40 degrees Celsius. Kinetics showed that the adsorption of metal ions in the opening minutes of rapid reaction kinetics has gradually reduced slope. The highest metal removal is performed in the first 15 minutes and then slowly continued adsorption and equilibrium within 90 minutes. This is especially important in an industry that in a very short time the bacteria can remove more metal from an aqueous solution. Isogram Langmuir described the adsorption of cadmium and nickel metals well by equilibrium experimental data. Conclusion: Results showed that maximum absorption of metal uptake (maximum adsorption capacity of the adsorbent) in about 0/5 and 0/7 mmol per gram (mmol / g) dry absorbent. SEM analysis showed that the metals were absorbed by bacterial surface groups. After contact with the bacterium, the surface shape of the bacterium changed. Most of the adsorption of metals is inactive, so this adsorbent can be used dead and inactive.

Background and Objective: HBsu protein in Bacillus subtilis is a member of histone like protein family HU. The protein has an important role in structure and function of bacterial nucleoid. In sights of its importance and similarity between the members of HU family, in this study the purified expressed HBsu, as an immunogen, was injected in rabbit until the produced polyclonal antiserum was used in the next research about identification of the other HU family members.Materials and Methods: The recently expressed HBsu protein from hbs gene of Bacillus subtilis ATCC6633 was injected in two male rabbits according to a twenty-day schedule and immunoblotting was done for antiserum production checking.Results: After twenty days, the antiserum against HBsu was produced and the presence of the antiserum was confirmed by immunoblotting. Also, extracted histone like protein from Halobacillus karajenesis was used for checking of its ability in identification of HBsu like protein that the answer was positive.Conclusion: The used method was rapid and with high ability for antiserum production against HBsu protein. The similarity between Halobacillus karajenesis HU and Bacillus subtilis HBsu is enough for the identification of this HU by antiserum against HBsu.

Gomishan wetland is a natural ecosystem located in 35 km north west of Gorgan, in the west vicinity of Khajeh Nafas city and Gomishan. Twice sampling from 3 different geographic positions in dry and rainy seasons, led to the isolation of 224 isolates. For 57 isolates, halophilic and halotolerant behaviors and also optimum and growth range in different pH and temperatures were determined. Most of the moderately halophilic and halotolerant strains were capable of growing optimally in media with pH 8.5-9 and optimum growth temperatures ranging from<4 to 40oC. The isolates were examined for hydrolytic enzymes production. Most of the isolates showed lipase activites and a total of 15, 7 and 3 strains produced amylases, proteases and DNases, respectively. The enzymes could be useful in some industrial processes. 16S rDNA phylogenetic analysis were done for 55 strains. According to this analysis, strains were placed in 22 different genera: Achromobacter, Aeromicrobium, Altererythrobacter, Bacillus, Caenispirillum, Cyclobacterium, Erythrobacter, Halobacillus, Halomonas, Idiomarina, Jonesia, Marinobacter, Martelella, Nesiotobacter, Paenibacillus, Planococcus, Pseudomonas, Rheinheimera, Saccharospirillum, Stappia, Thalassospira and Vibrio.23% of these strains were haloalkalophilic bacteria and belonged to the Bacillus, Halobacillus, Halomonas, Idiomarina and Marinobacter. This was the first study on the culturable bacteria at Gomishan wetland, an area of considerable alkaline thalassohaline ecosystem.

Flotation is the most important method for processing sulfide copper ores. Due to the high cost and environmental hazards caused by the chemical reagents used in this process (collectors, frothers, pH regulators, depressants, etc.), the possibility of replacing all these reagents or at least some of them are of special importance through environmentally friendly methods such as bio-flotation using halophilic bacteria. These bacteria have the ability of growth and proliferation in salty media and relatively neutral pHs such as sea salty water. In this research work, the four types of halophilic bacteria Halobacillus sp., Alkalibacillus almallahensis, Marinobacter sp., and Alkalibacillus sp. are studied to replace frothers (MIBC and F7240), depressant (sodium metabisulfite), and pH regulator (lime) in sulfide copper flotation using a Denver laboratory flotation cell. The results obtained indicate that each of the four types of bacteria mentioned above along with collectors (gasoil, Z11, and C7240) as the only chemical reagents (bio-flotation + collector) can depress pyrite better than the bacteria-free mode (flotation + all chemical reagents). Iron recovery in tailings in the standard flotation test is 46.8%, which is, respectively, increased to 91.9%, 74.5%, 70.3%, and 76.9% using the halophilic bacteria of Halobacillus sp., Alkalibacillus almallahensis, Marinobacter sp., and Alkalibacillus sp. On the other hand, the recovery of chalcopyrite using the bio-flotation method is lower than its recovery using the flotation method. Copper recovery in the concentrate in the standard flotation test is 89.1%, which is reached to 58.8%, 71.4%, 62.5%, and 69.4%, respectively, using the above bacteria in the bio-flotation method.

Aran-Bidgol salt lake is one of the lakes in central desert zone of Iran and is largest playa in Iran. This lake has shape as like a triangle that top it is towards north. Base length this triangle is 35 Km and high it is 38 Km. Screening bacteria from different points Aran-Bidgol salt lake, led to the isolation of 61 Gram-positive halophilic bacteria and 22 Gram-negative bacteria able to produce different hydrolytic enzymes. These strains are able to grow optimally in media with 5-15 % salts, 35-37°C temperature and pH 7.2. Strains No. 32, 20, 27, 40, 40, 9, 11, 24, 16 and 20 were produced amylase, protease, lipase, DNase, inulinase, xylanase, carboxy methyl cellulase, pectinase, pullulanase and chitinase. It is interesting that combined hydrolytic activities have been detected in some strains. DNase, indulines were the most enzymes produced in Grampositive bacilli and Gram- negative bacteria, lipase and Gram-positive cocci, pullulanase, carboxy methyl cellulase. Among these isolates, several strains with the ability to produce different valuable enzymes were selected, including AMB1(8 enzymes); AMB7, AMBI0, AMB12(7 enzymes); AMB5, AMB6, AMB11, AMB13(6 enzymes); AMB2, AMB3, AMB8, AMB9(5 enzymes); AMB4, AMGl(4 enzymes); AMCl, AMC2(3 enzymes); AMC3, AMC8, AMCI7, AMG2 (2 enzymes); AMG3(1 enzymes). Selected strains, after more accurate physiological and biochemical studies were identified regarding phylogeny and molecular characteristics using 16S rRNA technique. Sequencing 16SrRNA was performed to complete the identification process, which Gram-positive bacteria were belong to Halobacillus, Thalassobacillus, Bacillus, Salinicoccus and Gram-negative bacteria were belong to ldiomarina, Salicola and Halomonas.

Incheh Borun hypersaline wetland is located near the border of Turkmenistan,in north of Iran. This wetland is remarkable because of salinity and variation in pH range. sampling was carried out from soil, water and salt in September 2010. 400 strains were purified and 55 strains were selected randomly for PCR. Genera: Bacillus (18%), Marinobacter (16%), Halomonas (16%), Kocuria (9%), Oceanobacillus (7%), Dietzia (7%), Virgibacillus (6%), Chromohalobacter (5%), Rhodococcus (2%), Micrococcus (3%), Paenibacillus (2%), Halobacillus (3%), Thalassobacillus (2%), Arthrobacter (2%) and Desmospora (2%) were isolated 13 strains showing 97-98.4 % similarity and 7 strains had less than 97% similarity in 16S rRNA sequencing which is showed significant differences in the level of species or even genus. Optimum growth for salt was evaluated and 22 strains were moderate halophile and 33 strains were halotolerant. Producing 4 hydrolytic enzymes was evaluated which the main producers of hydrolytic enzymes were Gram-positive bacilli and the most frequent enzyme was Gelatinase and Protease.