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    Anoxybacillus kamchatkensis subsp asaccharedens subsp nov., a thermophilic bacterium isolated from a hot spring in Batman
    (Microbiol Res Foundation, 2008) Gul-Guven, Reyhan; Guven, Kemal; Poli, Annarita; Nicolaus, Barbara
    A new thermophilic spore-forming strain KG8(T) Was isolated from the mud of Taslidere hot spring in Batman. Strain KG8(T) was aerobe, Gram-positive, rod-shaped, motile, occurring in pairs or filamentous. Growth was observed from 35-65 degrees C (optimum 55 degrees C) and at pH 5.5-9.5 (optimum pH 7.5). It was capable of utilizing starch, growth was observed until 3% NaCl (w/v) and it was positive for nitrate reduction. On the basis of 16S rRNA gene sequence similarity, strain KG8(T) was shown to be related most closely to Anoxybacillus species. Chemotaxonomic data (major isoprenoid quinone-menaquinone-7; major fatty acid-iso-C15:0 and iso-C17:0) supported the affiliation of strain KG8(T) to the genus Anoxybacillus. The results of DNA-DNA hybridization, physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain KG8(T). Based on these results we propose assigning a novel subspecies of Anoxybacillus kamchatkensis, to be named Anoxybacillus kamchatkensis subsp. asaccharedens subsp. nov. with the type strain KG8(T) (DSM 18475(T)=CIP 109280(T)).
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    Biosorption of Cd, Cu, Ni, Mn and Zn from aqueous solutions by thermophilic bacteria, Geobacillus toebii sub.sp decanicus and Geobacillus thermoleovorans sub.sp stromboliensis: Equilibrium, kinetic and thermodynamic studies
    (Elsevier Science Sa, 2009) Ozdemir, Sadin; Kilinc, Ersin; Poli, Annarita; Nicolaus, Barbara; Guven, Kemal
    Biosorption of each of the ions Cd2+, Cu2+, Ni2+, Zn2+ and Mn2+ on Geobacillus toebii sub.sp. decanicus (G1) and Geobacillus thermoleovorans sub.sp. stromboliensis (G2) in a batch stirred system was investigated. The equilibrium adsorptive quantity was determined to be a function of the solution pH, contact time, biomass concentration, initial metal concentrations and temperature. The results obtained from biosorption experiments are used to understand the driving forces that govern the interaction between metal ions and a biosorbent. The experimental results were fitted well to the Scatchard plot, Langmuir, Freundlich, Dubinin-Radushkevich (D-R) isotherms. According to the parameters of the Langmuir isotherms, the maximum biosorption capacities of Cd2+, Cu2+, Ni2+, Zn2+ and Mn2+ for G2 were 38.8, 41.5, 42, 29 and 23.2 mg/g, respectively, while 29.2, 48.5, 21, 21.1 and 13.9 mg/g for G1, respectively. The mean free energy values evaluated from the D-R model indicated that the biosorptions of studied heavy metal ions onto bacteria were taken place by physical interaction. The biosorption mechanisms of studied metal ions on to the biosorbents were analysed by FT-IR spectra of G1 and G2 with and without metal ions. The first order and second order coefficients were obtained at 298, 308, 318 and 343 K. The experimental results were used to calculate the thermodynamic parameters. (C) 2009 Elsevier B.V. All rights reserved.
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    Biosorption of Heavy Metals (Cd2+, Cu2+, Co2+, and Mn2+) by Thermophilic Bacteria, Geobacillus thermantarcticus and Anoxybacillus amylolyticus: Equilibrium and Kinetic Studies
    (Taylor & Francis Inc, 2013) Ozdemir, Sadin; Kilinc, Ersin; Poli, Annarita; Nicolaus, Barbara
    Two strains of thermophilic bacteria, Geobacillus thermantarcticus and Anoxybacillus amylolyticus, were employed to investigate the biosorption of heavy metals including Cd2+, Cu2+, Co2+, and Mn2+ ions. The effects of different biosorption parameters such as pH (2.010.0), initial metal concentrations (10.0300.0mg L-1), amount of biomass (0.2510g L-1), temperature (3080 degrees C), and contact time (15120min) were investigated. Concentrations of metal ions were determined by using an inductively coupled plasma optical emission spectrometry (ICP-OES). Optimum pHs for Cd2+, Cu2+, Co2+, and Mn2+ biosorption by Geobacillus thermantarcticus were found to be 4.0, 4.0, 5.0, and 6.0, respectively. For Anoxybacillus amylolyticus, the optimum pHs for Cd2+, Cu2+, Co2+, and Mn2+ biosorption were found to be 5.0, 4.0, 5.0, and 6.0, respectively. The Cd2+, Cu2+, Co2+, and Mn2+ removals at 50mg L-1 in 60min by 50mg dried cells of Geobacillus thermantarcticus were 85.4%, 46.3%, 43.6%, and 65.1%, respectively, whereas 74.1%, 39.8%, 35.1%, and 36.6%, respectively, for Anoxybacillus amylolyticus. The optimum temperatures for heavy metal biosorption were near the optimum growth temperatures for both strains. Scatchard plot analysis was employed to obtain more compact information about the interaction between metal ions and biosorbents. The plot results were further studied to determine if they fit Langmuir and Freundlich models.
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    Cd, Cu, Ni, Mn and Zn resistance and bioaccumulation by thermophilic bacteria, Geobacillus toebii subsp decanicus and Geobacillus thermoleovorans subsp stromboliensis
    (Springer, 2012) Ozdemir, Sadin; Kilinc, Ersin; Poli, Annarita; Nicolaus, Barbara; Guven, Kemal
    Bioaccumulation and heavy metal resistance of Cd2+, Cu2+, Ni2+, Zn2+ and Mn2+ ions by thermophilic Geobacillus toebii subsp. decanicus and Geobacillus thermoleovorans subsp. stromboliensis were investigated. The metal resistance from the most resistant to the most sensitive was found as Mn > Ni > Cu > Zn > Cd for both Geobacillus thermoleovorans subsp. stromboliensis and Geobacillus toebii subsp. decanicus. It was determined that the highest metal bioaccumulation was performed by Geobacillus toebii subsp. decanicus for Zn (36,496 mu g/g dry weight cell), and the lowest metal bioaccumulation was performed by Geobacillus toebii subsp. decanicus for Ni (660.3 mu g/g dry weight cell). Moreover, the dead cells were found to biosorbe more metal in their membranes compared to the live cells. In the presence of 7.32 mg/l Cd concentration, the levels of Cd absorbed in live and dead cell membranes were found as 17.44 and 46.2 mg/g membrane, respectively.
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    Geobacillus galactosidasius sp nov., a new thermophilic galactosidase-producing bacterium isolated from compost
    (Elsevier Gmbh, 2011) Poli, Annarita; Laezza, Giusi; Gul-Guven, Reyhan; Orlando, Pierangelo; Nicolaus, Barbara
    Two thermophilic spore-forming strains, with optimum growth temperature at 70 degrees C, were isolated from compost of the Experimental System of Composting (Teora, Avellino, Italy). A phylogenetic analysis based on 16S rRNA gene sequences showed that these organisms represented a new species of the genus Geobacillus. Based on polyphasic taxonomic data the strains represented a novel species for which the name Geobacillus galactosidasius sp. nov. is proposed. The type strain is CF1B(T) (=ATCC BAA-1450(T) = DSM 18751(T)). (C) 2011 Elsevier GmbH. All rights reserved.
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    Purification and some properties of a ?-galactosidase from the thermoacidophilic Alicyclobacillus acidocaldarius subsp rittmannii isolated from Antarctica
    (Elsevier Science Inc, 2007) Gul-Guven, Reyhan; Guven, Kemal; Poli, Annarita; Nicolaus, Barbara
    An intracellular beta-galactosidase from a thermoacidophilic A licyclobacillus acidocaldarius subsp. rittmannii was purified by procedures including precipitation with ammonium sulphate, gel permeation, ion-exchange and affinity chromatography and finally by preparative electrophoresis and some properties of the purified enzyme were determined. The homogenous enzyme had a specific activity of 113 U/mg protein, with a fold purification of 163 and a yield of 8%. The Km and kcat values for ONPG were determined as 8.9 mM and 1074 min(-1), respectively in the purified beta-galactosidase from A. acidocaldarius subspecies rittmannii. The bacteria produce thermostable P-galactosidase (EC 3.2.1.23) activity, which exhibits its optimum at the neutral pH region. The pH and temperature optima for the purified enzyme are 6.0 and 65 degrees C, respectively (10 min assay). beta-Galactosidase specific activities of crude extracts obtained from bacterial cells grown in the presence and absence of lactose over a period of time (6-40 h) showed that beta-galactosidase synthesis seems to be constitutive and increases by increasing time up to 40 h of cultivation. beta-Galactosidase activity in the bacteria growing on the medium without lactose was 0.4 U/mg protein and increased up to 0.6 U/mg protein in the cells growing on the medium with lactose at 24 h (an increase by about 33% of its constitutive value), while it was 0.072 and 0.48 U/mg protein, respectively at 12 h (an increase by about 85% of its constitutive value). IPTG was also found to increase beta-galactosidase activity over a short period of time. The molecular mass of the purified enzyme determined by gel filtration on FPLC and SDS-PAGE was 165 and 76 kDa, respectively. The beta-galactosidase from Alicyclobacillus acidocaldarius subsp. rittmannii is most likely to belong to the glycoside hydrolyse family 42. (C) 2006 Elsevier Inc. All rights reserved.
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    Resistance and bioaccumulation of Cd2+, Cu2+, Co2+ and Mn2+ by thermophilic bacteria, Geobacillus thermantarcticus and Anoxybacillus amylolyticus
    (Springer, 2013) Ozdemir, Sadin; Kilinc, Ersin; Nicolaus, Barbara; Poli, Annarita
    In this study, bioaccumulation and heavy metal resistance of Cd2+, Cu2+, Co2+ and Mn2+ ions by thermophilic Geobacillus thermantarcticus and Anoxybacillus amylolyticus was investigated. The bacteria, in an order with respect to metal resistance from the most resistant to the most sensitive, was found to be Mn2+ > Co2+ > Cu2+ > Cd2+ for both G. thermantarcticus and A. amylolyticus. It was determined that the highest metal bioaccumulation was performed by A. amylolyticus in Mn2+ (28,566 mu g/g dry weight), and the lowest metal bioaccumulation was performed by A. amylolyticus in Co2+ (327.3 mu g/g dry weight). The highest Cd2+ capacities of dried cell membrane was found to be 36.07 and 39.55 mg/g membrane for G. thermantarticus and A. amylolyticus, respectively, and the highest Cd2+ capacities of wet cell membrane was found to be 14.36 and 12.39 mg/g membrane for G. thermantarcticus and A. amylolyticus, respectively.