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A strain designated GUMF5 was isolated in Goa-India from sediments of Dead Sea-Israel and identified as haloarchaeon Halomicroarcula pellucida based on 16S rRNA gene analysis similarity value of 99.84%. Strain GUMF5 grew on mineral salts medium with 20% NaCl and 0.5% carboxymethyl cellulose-sodium (CMC-Na) as a sole source of carbon and produced haloextremozyme cellulase. The enzyme was concentrated using Sephadex G20, precipitated with ethanol, dialyzed and retentate purified using Sephadex G200, the size exclusion chromatography. A yield of 78.53% cellulase with an activity of 131.13 U/mg and 1.24-fold purity was obtained. The purified cellulase had optimum activity at 20% NaCl, at 40 ºC, 0.5% CMC-Na, pH 7 and 150 rpm. SDS-PAGE combined with zymographic analysis revealed the molecular weight of cellulase as 240 kDa, 40 kDa and 17.4 kDa. The activity of the enzyme was stimulated by metallic cations in the order of Ca+2 > Mn+2 > Mg+2 > SO42− > NH4+ and was inhibited by Ag+ > Fe+2 > Cu+2. Methanol and ethanol enhanced the cellulase activity by 6% and 26%, respectively. The haloextremozyme cellulase degraded Whatman No. 1 filter paper indicated in scanning electron micrographs, exposure of open pores and fibers without any intra connectivity corresponding to paperase activity and implicating the possible use of enzyme to bio-convert cellulosic waste. Conclusively, Halomicroarcula pellucida GUMF5 (Accession number: MH244431), globally, is the only Halomicroarcula pellucida isolated from the sediments of Dead Sea producing haloextremozyme cellulase, and hence is an important biotechnological resource. [ABSTRACT FROM AUTHOR]

A strain designated GUMF5 was isolated in Goa-India from sediments of Dead Sea-Israel and identified as haloarchaeon Halomicroarcula pellucida based on 16S rRNA gene analysis similarity value of 99.84%. Strain GUMF5 grew on mineral salts medium with 20% NaCl and 0.5% carboxymethyl cellulose-sodium (CMC-Na) as a sole source of carbon and produced haloextremozyme cellulase. The enzyme was concentrated using Sephadex G20, precipitated with ethanol, dialyzed and retentate purified using Sephadex G200, the size exclusion chromatography. A yield of 78.53% cellulase with an activity of 131.13 U/mg and 1.24-fold purity was obtained. The purified cellulase had optimum activity at 20% NaCl, at 40 ºC, 0.5% CMC-Na, pH 7 and 150 rpm. SDS-PAGE combined with zymographic analysis revealed the molecular weight of cellulase as 240 kDa, 40 kDa and 17.4 kDa. The activity of the enzyme was stimulated by metallic cations in the order of Ca+2 > Mn+2 > Mg+2 > SO42− > NH4+ and was inhibited by Ag+ > Fe+2 > Cu+2. Methanol and ethanol enhanced the cellulase activity by 6% and 26%, respectively. The haloextremozyme cellulase degraded Whatman No. 1 filter paper indicated in scanning electron micrographs, exposure of open pores and fibers without any intra connectivity corresponding to paperase activity and implicating the possible use of enzyme to bio-convert cellulosic waste. Conclusively, Halomicroarcula pellucida GUMF5 (Accession number: MH244431), globally, is the only Halomicroarcula pellucida isolated from the sediments of Dead Sea producing haloextremozyme cellulase, and hence is an important biotechnological resource. [ABSTRACT FROM AUTHOR]

We study the earthquake response of the Zevulun Valley basin, underlying northern Israel's largest urban area, with 2D viscoelastic seismic modeling of a detailed geological section. We found that amplification of the horizontal vibrations, the ratio of basin to no-basin response spectra, correlates with basin depth. In the deepest portion of the basin (Qishon graben), long periods (2-5 sec) are amplified by 400%; in the shallowest portion of the basin (Afeq horst), shorter periods (~0.5 sec) are amplified by 300%-400%. These resonances in the vertical direction through the basin are strong enough that their amplitude overwhelms the amplitude of a previously recognized basin-edge effect. The horizontal/vertical (H/V) Fourier spectral ratios based on 124 ambient noise measurements do not fully coincide with the basin to no-basin Fourier spectral ratios of the simulation, but the resonance frequencies found in both methods are alike. Moreover, the relation between the resonance frequency and the depth of the corresponding seismic reflector in the simulation is almost identical to the empirical frequency-depth relations obtained from measurements. This indicates that the average shear-wave velocity of the sedimentary column in the model is consistent with measurements. To evaluate the necessity of 2D analysis, we performed additional ID simulations at two locations along the section. For the Qishon graben, 1D analysis underestimates the amplification factor relative to 2D by 25%, whereas for the Afeq horst, ID and 2D simulations are similar. For a hard layer within the soft Qishon graben fill, we found that when the hard layer is thinner than ~50 m, its influence on ground motion is small. [ABSTRACT FROM AUTHOR]