Characterization of a xylanase from a thermophilic strain of Anoxybacillus pushchinoensis A8

Abstract

A facultatively anaerobic, thermophilic, xylanolytic bacterium was isolated from a sample collected from the Diyadin Hot Springs, Turkey. According to morphological, biochemical and molecular identification, this new strain was suggested to be representative of the Anoxybacillus pushchinoensis and it was designated as Anoxybacillus pushchinoensis strain A8. It exhibited 97% similarity to 16S rRNA gene sequence of A. pushchinoensis and 77% DNA homology by DNA-DNA hybridization studies. Q-sepharose and CM-sepharose chromatography was used to purify an extracellular xylanase to >90% purity from this species. The enzyme had a molecular mass of approximately 83 kDa. The enzyme showed optimum activity at pH 6.5 and it was 96% stable over a broad pH range of 6.5-11 for 24 hours. The enzyme had optimum activity at 55• C and it was 100% stable at temperature between 50-60• C up to 24 hours. Kinetic characterization of the enzyme was performed at temperature optima (55 • C) and Vmax and Km were found to be 59.88 U/mg protein and 0.909 mg/mL, respectively. Oat spelt xylan but not xylooligosaccharides was degraded by the enzyme and xylose was the only product detected from oat xylan degradation. This suggested that the enzyme was an exo-acting xylanase.

Production, Purification, and Characterization of Thermostable Alkaline Xylanase From Anoxybacillus kamchatkensis NASTPD13

“…The optimization of medium and culture conditions for maximum xylanase production was carried out by stepwise variation of physicochemical parameters of growth conditions of A. kamchatkensis NAST-PD13. Initially, the bacterial isolate was grown in various MSM containing 0.5% xylan as reported previously (Nakamura et al, 1993 ; Kacagan et al, 2008 ; Maki et al, 2011 ; Padilha et al, 2015 ) (data not shown). Nakamura and Horikoshi basal medium had been routinely used for the isolation of xylanase producing microorganisms.…”

“…Gels were then stained with 0.1% Congo red for 10 min and destained with 1 M NaCl until zones of clearing were seen. The gels were fixed with 5% acetic acid and photographed (Kacagan et al, 2008 ).…”

Flavobacterium suaedae sp. nov., an endophyte isolated from the root of Suaeda corniculata

“…Menaquinone 6 (MK-6) is the major respiratory quinone, while C 15 : 0 , iso-C 15 : 0 , iso-C 15 : 1 G, iso-C 15 : 0 3-OH, summed feature 3 (C 16 : 1 v7c and/or C 16 : 1 v6c), iso-C 16 : 0 3-OH, iso-C 17 : 1 v9c and iso-C 17 : 0 3-OH are the predominant fatty acids, and the genomic DNA G+C contents are in the range of 30-52 mol% (Bernardet & Bowman, 2006Bernardet et al, 1996). Species of the genus Flavobacterium have been isolated from various habitats, including seawater (Bhumika et al, 2013;Fu et al, 2011;Yi et al, 2005), freshwater (Chen et al, 2013;Kacagan et al, 2013;Kang et al, 2013;Kim et al, 2014;Lee et al, 2013;Qu et al, 2009), high-arsenic sediments (Ao et al, 2014), wastewater (Aslam et al, 2005;Liu et al, 2010;Yoon et al, 2009), soil (Dong et al, 2013a, b;Kim et al, 2006), farmland (Chen et al, 2014;Kim et al, 2006;Liu et al, 2008), river sludge (Zhang et al, 2015a), marine sediment (Fu et al, 2011;algae (Miyashita et al, 2010;Nedashkovskaya et al, 2014), compost (Kim et al, 2011(Kim et al, , 2012a, rhizosphere soil (Madhaiyan et al, 2010;Son et al, 2013;Xiao et al, 2011;Zhang et al, 2015b), a glacier (Zhang et al, 2006) and a plant (Kämpfer et al, 2015).…”

Taxonomic Classification of Anoxybacillus Isolates from Geothermal Regions in Turkey by 16S rRNA Gene Sequences and ARDRA, ITS-PCR, Rep-PCR Analyses

“…These thermozymes have been used in a number of industrial applications as they possess thermal stability to harsh industrial processes at high temperatures (Demirjian et al, 2001). Thermophilic bacilli are the natural source of many thermostable enzymes, and of those from thermophilic bacilli, some thermostable enzymes belonging to species from the genus Anoxybacillus such as amylase (Poli et al, 2006), glucosidase (Cihan et al, 2009), esterase (Colak et al, 2005), aldolase (Ertunga et al, 2007), proteinase (Lavrenteva et al, 2009) and xylanase (Kacagan et al, 2008) have been well characterized.…”