Thermostable alkaline protease from newly isolated Vibrio sp.: extraction, purification and characterisation

Biologia ◽  
2012 ◽  
Vol 67 (4) ◽  
Author(s):  
Ponnambalam Subhashini ◽  
Neelamegam Annamalai ◽  
Ayyappan Saravanakumar ◽  
Thangavel Balasubramanian

AbstractAn extracellular alkaline protease-producing Vibrio sp. was isolated from mangrove sediments of Vellar estuary. A 9.36-fold purification was achieved by a three-step purification procedure and the molecular weight of the enzyme was determined as 33 kDa by SDS-PAGE. The enzyme was active in a broad range of pH (6.0–11.0) and temperature (30–70°C), the optimum being at pH 9.0 and temperature 55°C. The enzyme was stable at alkaline pH range of 9–11 and up to a temperature of 60°C, after incubation for 1 h. Metals like Co2+, Hg2+, Ni2+ and Cu2+ inhibited the enzyme activity, whereas Fe2+, Ca2+ and Mn2+ were found to enhance the activity. The protease was found to be highly stable in the presence of oxidizing agents like H2O2, detergents such as SDS and Triton-X-100 and also some of the commonly used commercial detergents. The organic solvents like xylene, isopropanol, hexane and benzene were found to enhance as well as stabilize the enzyme activity. The extracellular production of the enzyme, the pH and thermal stability, and the stability in presence of oxidants, surfactants, commercial detergents and organic solvents, altogether suggest that it can be used as a laundry additive.

2021 ◽  
Vol 19 (3) ◽  
pp. 509-517
Author(s):  
Nguyen Khanh Hoang Viet ◽  
Ha Thi Thuy Hoa ◽  
Truong Nam Hai ◽  
Do Thi Huyen

A gene coding for GH5 endoglucanase exploited from metagnomic DNA data of bacteria in Vietnamese goats’ rumen was modularity structure including a catalytic module, a fibronectin-3 like module and an X module. The recombinant enzyme was sucessfully expressed in E. coli and purified.  To study the effect of some metal ions and chemicals on enzyme activity, in this study, we used some tools including Swiss-Prot, ProFunc, COFACTOR for prediction of enzyme structure and ligands interaction. The obtained results indicated that the most similar structure with enzyme had two conserved residues (Asp-190 và Asp-192) linked with Mn2+ within a radius of ~ 3.5 Å from the center of ion Mn2+ and enzyme molecule contained a disulphide bond. Experimental results for essessment of the effect of some metal ions (Ca2 +, Mn2 +, Mg2+, Ni2+, K+, Co2+, Cu2+, Zn2+, Fe3+) at the final concentration of 10 mM and of six common chemicals including SDS (1%), urea (1 µM), 2-mercaptoethanol (1 µM), EDTA (1 µM), tween 80 (1mM), triton X-100 (1 µM) showed that only Mn2+ increased enzyme activity slightly at concentration of 10 mM and two times at the concentration of 40 mM Mn2+. The Mn2+ has been identified as a specific binding agent may increase the stability and activity of endoglucanase GH5.


Molecules ◽  
2018 ◽  
Vol 23 (7) ◽  
pp. 1800 ◽  
Author(s):  
Nurfadhilah Eko Sukohidayat ◽  
Mohammad Zarei ◽  
Badlishah Baharin ◽  
Mohd Manap

Purification of lipase produced by L. mesenteroides subsp. mesenteroides ATCC 8293 was conducted for the first time using a novel aqueous two-phase system (ATPS) composed of Triton X-100 and maltitol. The partitioning of lipase was optimized according to several parameters including pH, temperature, and crude load. Results showed that lipase preferentially migrated to the Triton X-100 rich phase and optimum lipase partitioning was achieved in ATPS at TLL of 46.4% and crude load of 20% at 30 °C and pH 8, resulting in high lipase purification factor of 17.28 and yield of 94.7%. The purified lipase showed a prominent band on SDS-PAGE with an estimated molecular weight of 50 kDa. The lipase was stable at the temperature range of 30–60 °C and pH range of 6–11, however, it revealed its optimum activity at the temperature of 37 °C and pH 8. Moreover, lipase exhibited enhanced activity in the presence of non-ionic surfactants with increased activity up to 40%. Furthermore, results exhibited that metals ions such as Na+, Mg2+, K+ and Ca2+ stimulated lipase activity. This study demonstrated that this novel system could be potentially used as an alternative to traditional ATPS for the purification and recovery of enzymes since the purified lipase still possesses good process characteristics after undergoing the purification process.


2016 ◽  
Vol 88 (suppl 1) ◽  
pp. 479-487 ◽  
Author(s):  
YUPING MA ◽  
SIWEN SUN ◽  
HUI HAO ◽  
CHUNPING XU

ABSTRACT A soil isolate, Penicillium janthinellum sw09 has been found to produce significant amounts of an extracellular pectinase subsequently characterized as exo-polygalacturonase (exo-PG). By optimizing growth conditions, P. janthinellum sw09 produced high amount of exo-PG (16.54 units/mL). The crude enzyme was purified by gel filtration chromatography and two exo-PG activity peaks (designated as PGI and PGII) were revealed. On SDS-PAGE analysis, purified PGII using DEAE-Sepharose FF column, was found to be a single band with a molecular mass of 66.2 kDa. The purified PGII exhibited maximal activity at the temperature of 45 oC and pH 5.0. The stability profiles show that PGII is more stable in the pH range of 4.0-8.0 and below 60 oC. The Km and Vmax for the enzyme was 1.74 mg/mL and 18.08 μmol/ (mL•min), respectively. Due to this enzymatic characterization, this pectinase is an attractive candidate for applications in degradation of pectin.


2021 ◽  
Vol 12 ◽  
Author(s):  
Sonia Sharma ◽  
Shiv Kumar ◽  
Rajinder Kaur ◽  
Ramandeep Kaur

A newly isolated alkaline protease-producing myxobacterium was isolated from soil. The strain was identified as Pyxidicoccus sp. S252 on the basis of 16S rRNA sequence analysis. The extracellular alkaline proteases produced by isolate S252 (PyCP) was optimally active in the pH range of 11.0–12.0 and temperature range of 40–50°C The zymogram of PyCP showed six caseinolytic protease bands. The proteases were stable in the pH range of 8.0–10.0 and temperature range of 40–50°C. The activity of PyCP was enhanced in the presence of Na+, Mg2+, Cu2+, Tween-20, and hydrogen peroxide (H2O2) (hydrogen peroxide), whereas in Triton X-100, glycerol, ethylenediaminetetraacetic acid (EDTA), and Co2+, it was stable. PyCP showed a potential in various applications. The addition of PyCP in the commercial detergent enhanced the wash performance of the detergent by efficiently removing the stains of tomato ketchup and coffee. PyCP efficiently hydrolyzed the gelatin layer on X-ray film to release the embedded silver. PyCP also showed potent dehairing of goat skin and also efficiently deproteinized sea shell waste indicating its application in chitin extraction. Thus, the results of the present study indicate that Pyxidicoccus sp. S252 proteases have the potential to be used as an ecofriendly replacement of chemicals in several industrial processes.


Author(s):  
Peichuan Xing ◽  
Dan Liu ◽  
Wen-Gong Yu ◽  
Xinzhi Lu

Renibacteriumsp. QD1, a bacteria strain capable of hydrolysing chitosan, was isolated from the homogenate of small crabs. An extracellular chitosanase, Csn-A, was purified from the QD1 fermentation broth. The enzyme was purified to homogeneity, with a yield of eight-fold, 67% recovery and a specific activity of 1575 U/mg proteins. The molecular weight of Csn-A was estimated to be 26.1 kDa by SDS-PAGE. Unlike other chitosanases, the purified Csn-A displayed maximal activity at a pH range of 5.3–6.5, and it was stable in a broad pH range of 5.0–10.0. The optimum temperature for chitosanlytic activity was 55°C. The enzyme activity was strongly stimulated by Mn2+but inhibited by Fe3+, Cu2+, Al3+, Zn2+and SDS. TLC analysis demonstrated that Csn-A hydrolysed N-deacetylated polymeric glucosamines into chito-biose and -triose in an endo-type manner. The amino acid seuquence of Csn-A showed close identity with an uncharacterized chitosanase of strain ATCC33209.


2020 ◽  
Vol 10 (21) ◽  
pp. 7584
Author(s):  
Huijing Liu ◽  
Jie Liu ◽  
Tangbing Cui

β-mannanase is one of the key enzymes to hydrolyze hemicellulose. At present, most β-mannanases are not widely applied because of their low enzyme activity and unsuitable enzymatic properties. In this work, a new β-mannanase from Enterobacter aerogenes was studied, which laid the foundation for its further application. Additionally, we will further perform directed evolution of the enzyme to increase its activity, improve its temperature and pH properties to allow it more applications in industry. A new β-mannanase (Man26E) from Enterobacter aerogenes was successfully expressed in Escherichia coli. Man26E showed about 40 kDa on SDS-PAGE gel. The SWISS-MODEL program was used to model the tertiary structure of Man26E, which presented a core (α/β)8-barrel catalytic module. Based on the binding pattern of CjMan26 C, Man26E docking Gal1Man4 was investigated. The catalytic region consisted of a surface containing four solvent-exposed aromatic rings, many hydrophilic and charged residues. Man26E displayed the highest activity at pH 6.0 and 55 °C, and high acid and alkali stability in a wide pH range (pH 4–10) and thermostability from 40 to 50 °C. The enzyme showed the highest activity on locust bean gum, and the Km and Vmax were 7.16 mg mL−1 and 508 U mg−1, respectively. This is the second β-mannanase reported from Enterobacter aerogenes B19. The β-mannanase displayed high enzyme activity, a relatively high catalytic temperature and a broad range of catalytic pH values. The enzyme catalyzed both polysaccharides and manno-oligosaccharides.


2019 ◽  
Author(s):  
Chem Int

The kinetics of oxidation of methyl orange by vanadium(V) {V(V)} has been investigated in the pH range 2.3-3.79. In this pH range V(V) exists both in the form of decavanadates and VO2+. The kinetic results are distinctly different from the results obtained for the same reaction in highly acidic solution (pH < 1) where V(V) exists only in the form of VO2+. The reaction obeys first order kinetics with respect to methyl orange but the rate has very little dependence on total vanadium concentration. The reaction is accelerated by H+ ion but the dependence of rate on [H+] is less than that corresponding to first order dependence. The equilibrium between decavanadates and VO2+ explains the different kinetic pattern observed in this pH range. The reaction is markedly accelerated by Triton X-100 micelles. The rate-[surfactant] profile shows a limiting behavior indicative of a unimolecular pathway in the micellar pseudophase.


Author(s):  
Ю.И. Цой

Задача получения однородного состава ЛКМ сводится к правильному выбору пленкообразователей и соответствующих растворителей и, в случае необходимости, разбавителей и добавок. На основе положений теории растворимости была проведена оценка совместимости компонентов и стабильности таких систем. Критериями оценки были приняты параметры растворимости и термодинамического взаимодействия. Исследовали совместимость алкидных лаков с аминоформальдегидными смолами в бутаноле, и результаты этих исследований представлены в треугольной фазовой диаграмме. Для оценки совместимости смол по результатам расчета параметров термодинамического взаимодействия были построены спинодали для тройных систем. Как показывает анализ результатов проведенных исследований, даже при большой разности ?? = |?12 – ?13| = 0,2 наблюдается небольшая область несовместимости. С уменьшением разности ?? область несовместимости сужается. При ?23 > ?с область несовместимости расширяется как для ? = 0,2, так и для ?? = 0,1 и ?? = 0. Таким образом, для таких систем на совместимость компонентов, в первую очередь, влияет их взаимодействие между собой – чем оно больше, тем лучше они совместимы. Проведенные исследования показали, что парциальные параметры растворимости, учитывающие природу когезионных сил, более объективно характеризуют растворимость пленкообразующих смол в органических растворителях, чем их общий параметр растворимости. Растворимость пленкообразующих алкидных и этерифицированных аминоформальдегидных смол в органических растворителях обусловлена термодинамическим взаимодействием молекулярных сил различной природы. Стабильность смеси алкидной и этерифицированной аминоформальдегидной смолы в бутаноле обусловлена в большей степени термодинамическим взаимодействием молекулярных сил; при этом степень бутанолизации меламиноформальдегидной смолы оказывает наибольшее влияние на стабильность cистемы. Проведенные исследования по стабильности лакокрасочных смесей из различных пленкообразующих смол на основе рассмотренных критериев оценки могут быть использованы для совершенствования технологии защитно-декоративной отделки древесины. The problem of obtaining a homogeneous composition of the coatings is reduced to the proper selection of film-forming agents, and diluent and, if appropriate, diluents and additives. On the basis of the theory of solubility, we have carried out the assessment of the compatibility of the components and stability of such systems. The evaluation criteria were adopted the parameters of the solubility and thermodynamic interaction. Researched the compatibility with alkyd varnishes aminoformaldehyde resin in butanol, and the results of these studies are presented in the triangular phase diagram. To evaluate the compatibility of the resins according to the results of calculation of thermodynamic parameters of interaction were built spinodal for ternary systems. As the analysis of the results of the studies, even when the difference ??|?12 – ?13| = 0,2 there is a small area of incompatibility. With the decrease of the difference ? ? region incompatibility narrows. When ?23> ?с region incompatibility extends to ?? = 0,2, and for ?? = 0.1 and ?? = 0. Thus, for such systems, compatibility of components, primarily, affects their interaction with each other – the further away it is, the better they are compatible. Studies have shown that the partial solubility parameters, which take into account the nature of cohesive forces, more objectively characterize the solubility of film-forming resins in organic solvents than their total solubility parameter. The solubility and film-forming aminoformaldehyde esterified alkyd resins in organic solvents due to thermodynamic interaction of molecular forces of different nature. Тhe stability of the mixture and aminoformaldehyde esterified alkyd resin in butanol is generated largely by thermodynamic forces of molecular interaction; the degree of butanolate melamine-formaldehyde resin has the greatest effect on the stability of the system. Conducted research on the stability of the paint mixtures of various film-forming resins on the basis of the evaluation criteria can be used to improve the technology of protective and decorative wood finish.


Foods ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1097
Author(s):  
Laura González-Blanco ◽  
Yolanda Diñeiro ◽  
Andrea Díaz-Luis ◽  
Ana Coto-Montes ◽  
Mamen Oliván ◽  
...  

The objective of this work was to demonstrate how the extraction method affects the reliability of biomarker detection and how this detection depends on the biomarker location within the cell compartment. Different extraction methods were used to study the sarcoplasmic and myofibrillar fractions of the Longissimus thoracis et lumborum muscle of young bulls of the Asturiana de los Valles breed in two quality grades, standard (Control) or dark, firm, and dry (DFD) meat. Protein extractability and the expression of some of the main meat quality biomarkers—oxidative status (lipoperoxidation (LPO) and catalase activity (CAT)), proteome (SDS-PAGE electrophoretic pattern), and cell stress protein (Hsp70)—were analyzed. In the sarcoplasmic fraction, buffers containing Triton X-100 showed significantly higher protein extractability, LPO, and higher intensity of high-molecular-weight protein bands, whereas the TES buffer was more sensitive to distinguishing differences in the protein pattern between the Control and DFD meat. In the myofibrillar fraction, samples extracted with the lysis buffer showed significantly higher protein extractability, whereas samples extracted with the non-denaturing buffer showed higher results for LPO, CAT, and Hsp70, and higher-intensity bands in the electrophoretic pattern. These findings highlight the need for the careful selection of the extraction method used to analyze the different biomarkers considering their cellular location to adapt the extractive process.


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