34,430 research outputs found
Heterologous expression and enhanced production of β-1,4-glucanase of Bacillus halodurans C-125 in Escherichia coli
No full textBackground: Recombinant DNA technology enables us to produce proteins with desired properties and insubstantial amount for industrial applications. Endo-1, 4-β-glucanases (Egl) is one of the major enzyme involved in degradation of cellulose, an important component of plant cell wall. The present study was aimed at enhancing the production of endo-1, 4-β-glucanases (Egl) of Bacillus halodurans in Escherichia coli. Results: A putative Egl gene of Bacillus Halodurans was expressed in E. coli by cloning in pET 22b (+). On induction with isopropyl-b-d-1-thiogalactopyranoside, the enzyme expression reached upto ~20% of the cell protein producing 29.2 mg/liter culture. An increase in cell density to 12 in auto-inducing LB medium (absorbance at 600 nm) enhanced β-glucanase production up to 5.4 fold. The molecular mass of the enzyme was determined to be 39 KDa, which is nearly the same as the calculated value. Protein sequence was analyzed by CDD, Pfam, I TASSER, COACH, PROCHECK Servers and putative amino acids involved in the formation of catalytic, substrate and metal binding domains were identified. Phylogenetic analysis of the β-glucanases of B. halodurans was performed and position of Egl among other members of the genus Bacillus producing endo-glucanases was determined. Temperature and pH optima of the enzyme were found to be 60°C and 8.0, respectively, under the assay conditions. Conclusion: Production of endo-1, 4 β-glucanase enzymes from B. halodurans increased several folds when cloned in pET vector and expressed in E. coli. To our knowledge, this is the first report of high-level expression and characterization of an endo-1, 4 β-glucanases from B. halodurans.How to cite: Zeeshan N, Naz S, Naz S et al. Heterologous expression and enhanced production of β-1,4-glucanase of Bacillus halodurans C-125 in E. coli. Electron J Biotechnol 2018;34. https://doi.org/10.1016/j.ejbt.2018.05.001. Keywords: Bacillus halodurans, Cellulases, Cellulose hydrolysis, Degradation of cellulose, Endo-1, 4-β-glucanases, Expression analysis, Heterologous expression, In silico protein characterization, IPTG, pET expression system, Plant cell wal
Axonchium noreasum Naz & Ahmad, 2012, n. sp.
No full textAxonchium noreasum n. sp. (Figs. 13–14) Measurements. Table 7. Description. Female: Body curved ventrad upon fixation, tapering towards both extremities. Cuticle with fine transverse striations, 2–4 µm thick at mid body and 6–8 µm on tail. Lateral chords without distinct glandular bodies, about one-fifth to one-fourth of body width at mid body. Lateral, dorsal and ventral body pores indistinct. Lip region offset, about one-fifth to one-fourth of body width at neck base; lips separated. Amphids cupshaped, their aperture 0.8 times the lip region width. Odontostyle fusiform, 1.1–1.3 times the lip region width long, its aperture about one-third of its length. Guiding ring single, at about one lip region width from anterior end. Odontophore linear, 1.1–1.3 times the odontostyle length. Nerve ring at 21–25 % of neck length from anterior end. Anterior muscular part of pharynx separated from the posterior expanded part by a deep constriction the latter occupying about 52–64 % of the neck length and enclosed in muscle sheath with straight bundles. Cardia, tonguelike, about one-third to one-half of the corresponding body width long. Genital system mono-opisthodelphic. Anterior branch represented by a simple sac, 1.7–3.9 times the corresponding body width long and in most of the specimens filled with sperms. Posterior branch well developed; ovary reflexed, not reaching the oviduct-uterus junction, measuring 40–145 µm with oocytes arranged in a single row except near tip. Oviduct joining ovary subterminally, measuring 45–80 µm, consisting of a long slender part with prismatic cells and a slightly wider pars dilatata with clear lumen. Sphincter present at oviduct-uterus junction. Uterus measuring 80–100 µm, differentiated into three parts, distal expanded part with wide lumen, intermediate tubular part with narrow lumen and proximal wider part with wide lumen. Vulva transverse. Vagina bent posteriad, about two-thirds of the corresponding body width deep; pars proximalis vaginae 16–20 µm with almost straight walls; pars refringens vaginae absent; pars distalis vaginae 7–8 µm with rounded walls. Prerectum 3.5–6.5 times anal body width long. Rectum 1.2 –1.5 times anal body width long. Tail short rounded, hemispheroid to almost clavate, 0.9–1.2 times anal body width long; hyaline part about half of tail length. Caudal pores two on each side. Male: similar to female in general morphology, except for posterior region being more curved because of the presence of copulatory muscles. Spicules slender, 1.5–1.8 times the cloacal body width in length, the proximal deviation (range). Characters Bhalokpong population Shillong population Holotype female Paratype females Paratype males Females Males n 1 9 7 3 2 L (mm) 1.2 1.2 ± 0.05 (1.1–1.3) 1.2 ± 0.04 (1.2–1.3) 1.05 ± 0.05 1.10, 1.14 (1.03–1.06) a 46.5 45.9 ± 1.36 41.6 ± 2.01 39.7 ± 1.2 36.7, 40.7 (44.1–48.4) (39.9–43.2) (38–41.4) b 2.5 2.6 ± 0.14 (2.5–2.7) 2.7 ± 0.12 (2.7–2.8) 2.8 ± 0.2 (2.7–3.3) 2.7, 3.1 Odontophore length 10 10.4 ± 0.4 (10–11) 11 ± 1.60 (10–13) 9.3 ± 0.47 (9–10) 9, 9 continued. Characters Umiam Shillong population Digboi(Assam) Population Females Males Females Males n 5 3 6 2 L (mm) 1.34 ± 0.10 (1.2–1.5) 1.2 ± 0.04 (1.2–1.3) 1.2 ± 0.12 (1.0– 1.4) 1.2, 1.2 a 39.6 ± 3.01 (35.1–43.2) 42.6 ± 2.16 (39.9–45.2) 44.4 ± 4.29 (39.6–50.5) 45.1, 47.1 b 2.9 ±. 0.21 (2.7–3.2) 3.3 ± 0.24 (3.1–3.7) 2.9 ± 0.28 (2.7–3.4) 2.8, 3.2 c 59.8 ± 2.9 (57.7–64.9) 55.2 ± 0.47 (54.6–55.7) 61.1 ± 6.37 (51–68.3) 53.3, 57.5 c` 0.9 ±.06 (0.9–1.04) 1.02 ± 0.01 (1.0– 1.04) 0.9 ± 0.06 (0.9–1.05) 1.1, 1.2 V 52 ± 1.7 (49–53) - 51.7 ± 1.73 (49.1–54.6) - G 1 8.4 ± 1.36 (6.3±10.1) - 5.1 ± 0.79 (4.1–6.6) - G 2 17.1 ± 2.05 (13.7–18.7) - 12.8 ± 1.2 (6–7) - Lip region width 6.6 ± 0.47 (6–7) 7 5.8 ± 0.63 (6–7) 5, 6 Lip region height 3.6 ± 0.48 (3–4) 3.6 ± 0.47 (3–4) 3.3 ± 0.47 (3–4) 4, 4 Amphid aperture 5.3 ± 0.47 (5–6) 5 5.8 ± 0.68 (5–6) 5, 6 Odontostyle length 8.5 ± 0.86 (8–10) 8.6 ± 0.47 (8–9) 7.5 ± 0.49 (7–8) 7, 8 Odontophore length 10.0 10.5 ± 0.5 (10–11) 10 ±0 9, 10 Guiding ring from anterior end 9.0 9 6.8 ± 0.37 (6–7) 7, 8 Nerve ring from anterior end 96.2 ± 6.4 (90–105) 130 ±0 115 ± 4.47 (110–120) 110, 110 Neck length 401 ± 33.5 (350–450) 383 ± 25.7 (350–413) 409 ± 41.65 (375–500) 375, 440 Expanded part of pharynx 267 ± 33.6 (215–275) 207 ± 5.3 (208–213) 214 ± 40.66 (175–300) 182, 265 Cardia length 12.8 ± 1.16 (12–15) 13 ±0 12.5 ± 2.32 (10–17) 12, 15 Body width at mid body 33.2 ± 2.22 (30–35) 30.3 ± 1.24 (29–32) 27.5 ± 0.5 (26–28) 26, 28 Body width at neck base 32.2 ± 2.2 (30–36) 31 ± 0.81 (30–32) 28.1 ± 1.21 (27–30) 27, 27 Body width at anus/cloaca 22.8 ± 0.74 (22–24) 22.6 ± 0.47 (22–23) 20.3 ± 0.47 (20–21) 18, 20 Anterior genital branch 111 ± 18.60 (85–138) - 63.6 ± 10.2 (45–77) - Posterior genital branch 216 ± 43.5 (152–270) - 156 ± 5.38 (150–165) - Vaginal depth 20 ± 1.4 (20–25) - 19.13 ± 1.4 (18–22) - Vulva from anterior end 732 ± 75.43 (658–875) - 621 ± 75.7 (545–765) - Prerectum length 133 ± 20.8 (100–165) 138 ± 6.23 (130–145) 148 ± 28.3 (120–200) 195, 220 Rectum length 27.4 ± 2.72 (24–30) 30 24.8 ± 1.57 (23–28) 30 Tail length 22.2 ± 1.6 (21–25) 23.3 ± 0.47 (23–24) 20 ± 0.81 (19–21) 22,23 Spicules length - 39 ± 1.41 (37–401) - 30,32 Lateral guiding pieces - 10.6 ± 1.6 (9–13) - 9,10 Ventromedian supplements - 2 - 2 slender part about two-fifths of the total spicule length with curved ends, distal part comparatively robust and slightly arcuate. Lateral guiding pieces with bifid end, about one-fourth of the spicules length. Supplements consisting of an adcloacal pair and two spaced ventromedians, starting above the range of spicules. Prerectum 5.5–8.5 times cloacal body width long. Rectum 1.2–1.6 cloacal body width long. Tail short, conoid, broadly rounded with slight concavity on ventral side, 0.9–1.2 times cloacal body width long. Caudal pores two on each side. Type habitat and locality. From soil around the roots of teak tree (Tectona grandis), from reserve forest area near Bhalukpong check post, Bomdilla, Arunachal Pradesh, India. GPS coordinate 27.26684 / 92.43484; latitude 26 o 56 'N, longitude 92 o 36 'E. Other habitats and localities. From soil around the roots of: i) unidentified grasses and herbs from Seven Miles, Shillong, Meghalaya; ii) unidentified grasses and herbs from Umiam, Shillong, Meghalaya and, iii) forest area from Digboi, district Tinsukia, Assam, India. Type specimens. Holotype female on slide Axonchium noreasum n. sp. / 1; paratype females and males on slides Axonchium noreasum n. sp. / 2–15; deposited with the nematode collection of the Department of Zoology, Aligarh Muslim University, India. A paratype female and a male deposited with the nematode collection of the Universidad de Jaén, Spain. Etymology. The species name " noreasum " stands for "north–east", because all the populations were collected from north-eastern India. Diagnosis and relationships. Body 1.0– 1.3 mm long; lip region offset, lips separate; odontostyle 8–10 µm long; two parts of the pharynx separated from each other by deep constriction; vagina directed posteriorly; anterior uterine branch 46–95 µm in length; spicules slender, 30–36 µm or 1.5–1.8 times cloacal body width long, with proximal slender part about two-fifths of the total spicule length, with curved ends, and the distal part comparatively robust and slightly arcuate; lateral guiding pieces with bifid ends, about one-fourth of the spicule length, and two spaced ventromedian supplements. The new species is most closely related to A. siddiqii Coomans & Nair, 1975 in having a posteriorly directed vagina in females, and only two ventromedian supplements in males. It differs mainly in spicule shape (vs simple arcuate, with proximal slender part about one-third or less of spicule length, lacking curved ends [see fig. 11 D,G of Coomans & Nair, 1975). Although the new species is very similar to A. siddiqii but the shape of its spicules which so characteristic for species delimitation in the genus Axonchium, is distinctly different in the two species.Published as part of Naz, Tabbasam & Ahmad, Wasim, 2012, Description of two new and five known species of the genus Axonchium Cobb, 1920 (Nematoda: Dorylamida) from India with diagnostic compendia and keys to species of the genera Axonchium and Syncheilaxonchium Coomans & Nair, 1975, pp. 1-37 in Zootaxa 3264 on pages 27-32, DOI: 10.5281/zenodo.21507
Syncheilaxonchium Coomans & Nair 1975, n. comb.
No full textGenus Syncheilaxonchium Coomans & Nair, 1975 Coomans and Nair (1975) proposed the subgenus Syncheilaxonchium as one of the subgenera of the genus Axonchium Cobb, 1920 and differentiated it from other subgenera of this genus mainly in the presence of a continuous lip region with amalgamated lips. They (l.c.) designated Axonchium (Syncheilaxonchium) rotundum Thorne, 1964 as the type species and also included A. (S.) amalgans Thorne, 1939; A. (S.) asacculum Siddiqi, 1968; A. (S.) baldum Thorne, 1964; A. (S.). coomansi Nair, 1975; A. (S.). deconincki Nair, 1975; A. (S.) indicum Siddiqi, 1964 and A. (S.). nairi Altherr, 1974 under this subgenus. Andrássy (2009), while raising this subgenus to generic rank, transferred Axonchium banaticum Popovici, 1990 (= Syncheilaxonchium banaticum (Popovici, 1990) Andrássy, 2009) and Axonchium perplexans Siddiqi, 1995 (= Syncheilaxonchium perplexans (Siddiqi, 1995) Andrássy, 2009) to Syncheilaxonchium without giving any reason. Although A. banaticum has a continuous lip region and suitably fits under the generic diagnosis of Syncheilaxonchium; A. perplexans, because of its offset lip region, does not. Naz et al. (2007) described Axonchium sturhani and Axonchium parassaculum, from New Zealand and Ahmad & Naz (2010 b) described Axonchium singaporense from Singapore. These three species have a continuous lip region with amalgamated lips. The main distinguishing character between these two genera is the nature of the lip region:, Axonchium has an offset lip region and partly or distinctly separate lips whereas the lip region is continuous in Syncheilaxonchium and the lips are completely amalgamated. Because of the presence of continuous lip region with amalgamated lips, the above three species completely fit under the generic diagnosis of Syncheilaxonchium and hence are being transferred here to the genus Syncheilaxonchium as Syncheilaxonchium sturhani (Naz et al., 2007) n. comb.; S. parassaculum (Naz et al., 2007) n. comb. and S. singaporense (Ahmad & Naz, 2010 b) n. comb. With the transfer of these three species, the total number of valid species under Syncheilaxonchium comes to twelve. Diagnosis. Small to large-sized (0.9–2.9 mm) nematodes; body almost straight to open C-shaped upon fixation. Cuticle usually smooth which appears finely transversely striated at higher magnification; lateral chords with or without distinct glandular bodies. Lip region rounded, continuous with body conour; lips amalgamated. Odontostyle short fusiform; guiding ring usually simples; odontophore rod-like with thickened walls, usually equal to odontostyle length. Anterior part of pharynx more or less muscular, separated from the postertior part by deep constriction or a short isthmus. Female genital system mono-opisthodelphic with or without prevulval sac. Vulva transverse; pars refringens vaginae absent. Males with well-developed massive, straight to ventrally arcuate spicules; sclerotised, rod-like lateral guiding pieces with distal bifid ends and spaced ventromedian supplements. Tail bluntly rounded or slightly clavate, similar in sexes. Type species: Syncheilaxonchium rotundum (Thorne, 1964) Coomans & Nair, 1975 = Axonchium rotundum Thorne, 1964Published as part of Naz, Tabbasam & Ahmad, Wasim, 2012, Description of two new and five known species of the genus Axonchium Cobb, 1920 (Nematoda: Dorylamida) from India with diagnostic compendia and keys to species of the genera Axonchium and Syncheilaxonchium Coomans & Nair, 1975, pp. 1-37 in Zootaxa 3264 on page 35, DOI: 10.5281/zenodo.21507
Parametric transfer in a synchronously pumped optical parametric oscillator
No full textThe conditions for high fidelity parametric transfer of the pulse shape of a near-infrared pump pulse to a mid-infrared idler pulse of a synchronously pumped optical parametric oscillator are investigated theoretically and experimentally
Measurement of the ratio of branching fractions B(B0→K∗0γ )/B(B0s→φγ ) and the directCP asymmetry inB 0→K∗0γ
No full textThe ratio of branching fractions of the radiative B decays B0→K⁎0γ and B0s→ϕγ has been measured using an integrated luminosity of 1.0 fb−1 of pp collision data collected by the LHCb experiment at a centre-of-mass energy of s√=7TeV. The value obtained is
B(B0→K⁎0γ)B(B0s→ϕγ)=1.23±0.06(stat.)±0.04(syst.)±0.10(fs/fd),
where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is associated with the ratio of fragmentation fractions fs/fd. Using the world average value for B(B0→K⁎0γ), the branching fraction B(B0s→ϕγ) is measured to be (3.5±0.4)×10−5.
The direct CP asymmetry in B0→K⁎0γ decays has also been measured with the same data and found to be
ACP(B0→K⁎0γ)=(0.8±1.7(stat.)±0.9(syst.))%.
Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations
Measurement of b-hadron masses
No full textMeasurements of b-hadron masses are performed with the exclusive decay modes B +→J/ψK +, B 0→J/ψK +, B0→J/ψKS0, Bs0→J/ψφ and Λb0→J/ψΛ using an integrated luminosity of 35pb -1 collected in pp collisions at a centre-of-mass energy of 7 TeV by the LHCb experiment. The momentum scale is calibrated with J/ψ→μ +μ - decays and verified to be known to a relative precision of 2 ×10 -4 using other two-body decays. The results are more precise than previous measurements, particularly in the case of the Bs0 and Λb0 masses
Observations of Bºs→ψ(2S)η and Bº(s)→ψ(2S)π+π- decays
No full textFirst observations of the B0s
→ψ(2S)η, B0 →ψ(2S)π
+
π
− and B0s
→ψ(2S)π
+
π
− decays are made
using a dataset corresponding to an integrated luminosity of 1.0 fb−1 collected by the LHCb experiment in
proton–proton collisions at a centre-of-mass energy of
√
s = 7 TeV. The ratios of the branching fractions
of each of the ψ(2S) modes with respect to the corresponding J/ψ decays are
B(B0s
→ψ(2S)η)
÷
B(B0s
→J/ψη)
= 0.83± 0.14 (stat)±0.12 (syst) ±0.02 (B),
;
B(B0→ψ(2S)π
+
π
−
)
÷
B(B0→J/ψπ
+
π
−
)
= 0.56± 0.07 (stat)±0.05 (syst)± 0.01 (B),
;
B(B0s
→ψ(2S)π
+
π
−
)
÷
B(B0s
→J/ψπ
+
π
−
)
= 0.34± 0.04 (stat)±0.03 (syst)± 0.01 (B),
where the third uncertainty corresponds to the uncertainties of the dilepton branching fractions of the J/ψ
and ψ(2S) meson decays
Branching fraction and CP asymmetry of the decays B+→K0Sπ+ and B+→K0SK+
No full textAn analysis of B+ → K0
Sπ+ and B+ → K0
S K+ decays is performed with the LHCb experiment. The pp
collision data used correspond to integrated luminosities of 1 fb−1 and 2 fb−1 collected at centre-ofmass
energies of
√
s = 7 TeV and
√
s = 8 TeV, respectively. The ratio of branching fractions and the
direct CP asymmetries are measured to be B(B+ → K0
S K+
)/B(B+ → K0
Sπ+
) = 0.064 ± 0.009 (stat.) ±
0.004 (syst.), ACP(B+ → K0
Sπ+
) = −0.022 ± 0.025 (stat.) ± 0.010 (syst.) and ACP(B+ → K0
S K+
) =
−0.21 ± 0.14 (stat.) ± 0.01 (syst.). The data sample taken at
√
s = 7 TeV is used to search for
B+
c
→ K0
S K+ decays and results in the upper limit ( fc · B(B+
c
→ K0
S K+
))/( fu · B(B+ → K0
Sπ+
)) <
5.8 × 10−2 at 90% confidence level, where fc and fu denote the hadronisation fractions of a ¯b
quark
into a B+
c or a B+ meson, respectively
Evidence for the decay B0→J/ψω and measurement of the relative branching fractions of meson decays to J/ψη and J/ψη′
No full textFirst evidence of the B 0 → J / ψ ω decay is found and the B s 0 → J / ψ η and B s 0 → J / ψ η ′ decays are studied using a dataset corresponding to an integrated luminosity of 1.0 fb -1 collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV. The branching fractions of these decays are measured relative to that of the B 0 → J / ψ ρ 0 decay:frac(B (B 0 → J / ψ ω), B (B 0 → J / ψ ρ 0)) = 0.89 ± 0.19 (stat) - 0.13 + 0.07 (syst),frac(B (B s 0 → J / ψ η), B (B 0 → J / ψ ρ 0)) = 14.0 ± 1.2 (stat) - 1.5 + 1.1 (syst) - 1.0 + 1.1 (frac(f d, f s)),frac(B (B s 0 → J / ψ η ′), B (B 0 → J / ψ ρ 0)) = 12.7 ± 1.1 (stat) - 1.3 + 0.5 (syst) - 0.9 + 1.0 (frac(f d, f s)), where the last uncertainty is due to the knowledge of f d / f s, the ratio of b-quark hadronization factors that accounts for the different production rate of B 0 and B s 0 mesons. The ratio of the branching fractions of B s 0 → J / ψ η ′ and B s 0 → J / ψ η decays is measured to befrac(B (B s 0 → J / ψ η ′), B (B s 0 → J / ψ η)) = 0.90 ± 0.09 (stat) - 0.02 + 0.06 (syst)
Measurement of the CKM angle gamma from a combination of B->Dh analyses
No full textA combination of three LHCb measurements of the CKM angle gamma is presented. The decays B->DK and B->Dpi are used, where D denotes an admixture of D0 and D0-bar mesons, decaying into K+K-, pi+pi-, K+-pi-+, K+-pi-+pi+-pi-+, KSpi+pi-, or KSK+K- final states. All measurements use a dataset corresponding to 1.0 fb-1 of integrated luminosity. Combining results from B->DK decays alone a best-fit value of gamma = 72.0 deg is found, and confidence intervals are set gamma in [56.4,86.7] deg at 68% CL, gamma in [42.6,99.6] deg at 95% CL. The best-fit value of gamma found from a combination of results from B->Dpi decays alone, is gamma = 18.9 deg, and the confidence intervals gamma in [7.4,99.2] deg or [167.9,176.4] deg at 68% CL, are set, without constraint at 95% CL. The combination of results from B->DK and B->Dpi decays gives a best-fit value of gamma = 72.6 deg and the confidence intervals gamma in [55.4,82.3] deg at 68% CL, gamma in [40.2,92.7] deg at 95% CL are set. All values are expressed modulo 180 deg, and are obtained taking into account the effect of D0-D0bar mixing
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