scholarly journals A Swollenin From Talaromyces leycettanus JCM12802 Enhances Cellulase Hydrolysis Toward Various Substrates

2021 ◽  
Vol 12 ◽  
Author(s):  
Honghai Zhang ◽  
Yuan Wang ◽  
Roman Brunecky ◽  
Bin Yao ◽  
Xiangming Xie ◽  
...  

Swollenins exist within some fungal species and are candidate accessory proteins for the biodegradation of cellulosic substrates. Here, we describe the identification of a swollenin gene, Tlswo, in Talaromyces leycettanus JCM12802. Tlswo was successfully expressed in both Trichoderma reesei and Pichia pastoris. Assay results indicate that TlSWO is capable of releasing reducing sugars from lichenan, barley β-glucan, carboxymethyl cellulose sodium (CMC-Na) and laminarin. The specific activity of TlSWO toward lichenan, barley β-glucan, carboxymethyl cellulose sodium (CMC-Na) and laminarin is 9.0 ± 0.100, 8.9 ± 0.100, 2.3 ± 0.002 and 0.79 ± 0.002 U/mg, respectively. Additionally, TlSWO had disruptive activity on Avicel and a synergistic effect with cellobiohydrolases, increasing the activity on pretreated corn stover by up to 72.2%. The functional diversity of TlSWO broadens its applicability in experimental settings, and indicating that it may be a promising candidate for future industrial applications.

Author(s):  
Selfela Restu Adina ◽  
Antonius Suwanto ◽  
Anja Meryandini ◽  
Esti Puspitasari

Abstract Background Lipases are promising biocatalysts for industrial applications and attract attention to be explored. A novel acidic lipase has been isolated from the lipolytic bacteria Micrococcus luteus EMP48-D (LipEMP48-D) screened from tempeh. The lipase gene had previously been overexpressed in Escherichia coli BL21, but the expression level obtained was relatively low. Here, to improve the expression level, the lipase gene was cloned to Pichia pastoris. We eliminated the native signal sequence of M. luteus and replaced it with α-mating factor (α-MF) signal sequence. We also optimized and synthesized the lipase gene based on codon preference in P. pastoris. Results LipEMP48-D lipase was expressed as an extracellular protein. Codon optimization has been conducted for 20 codons, with the codon adaption index reaching 0.995. The highest extracellular lipase activity obtained reached 145.4 ± 4.8 U/mg under AOX1 promoter in P. pastoris KM71 strain, which was 9.7-fold higher than the previous activity in E. coli. LipEMP48-D showed the highest specific activity at pH 5.0 and stable within the pH range 3.0–5.0 at 40 °C. LipEMP48-D also has the capability of hydrolyzing various long-chain triglycerides, particularly olive oil (100%) followed by sunflower oil (88.5%). LipEMP48-D exhibited high tolerance for various polar organic solvents with low log P, such as isopropanol (115.7%) and butanol (114.6%). The metal ions (Na+, K+, Ca2+, Mg2+, Mn+) decreased enzyme activity up to 43.1%, while Fe2+ increased relative activity of enzymes up to 200%. The conversion of free fatty acid (FFA) into fatty acid methyl ester (FAME) was low around 2.95%. Conclusions This study was the first to report overexpression of Micrococcus lipase in yeast. The extracellular expression of this acidic lipase could be potential for biocatalyst in industrial fields, especially organic synthesis, food industry, and production of biodiesel.


Minerals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 796
Author(s):  
Kaile Zhao ◽  
Chao Ma ◽  
Guohua Gu ◽  
Zhiyong Gao

The study of the depression effect of non-toxic depressants on the flotation separation of chalcopyrite from galena is of great importance for both industrial applications and theoretical research. The mixed depressant (DFinal) of four common inhibitors—sodium carboxymethyl cellulose, sodium silicate, sodium sulfite, and zinc sulfate—exhibited high selectivity during the separation of chalcopyrite from galena. Flotation tests on an industrial copper–lead bulk concentrate showed that using this depressant mixture can achieve highly efficient separation of chalcopyrite from galena at the natural pH of the pulp. Copper and lead concentrates were produced at grades of 21.88% (Cu) and 75.53% (Pb), with recoveries of 89.07% (Cu) and 98.26% (Pb). This showed a similar performance of DFinal with dichromate, which is a depressant that is widely used in industry, but without the environmental risks or the need for pH control. Zeta potential and Fourier transform infrared (FT-IR) results showed that interaction between the surface of the chalcopyrite and the mixed depressant was prevented by pre-treatment with a composite thiophosphate collector (CSU11), while the mixed depressant could expel/replace the composite thiophosphate on the surface of galena by chemical adsorption, depressing its flotation. This is the reason why this non-toxic depressant achieved the selective depression of galena from chalcopyrite, leading to efficient flotation separation.


2018 ◽  
Vol 57 (44) ◽  
pp. 15046-15053 ◽  
Author(s):  
Jiyu Yang ◽  
Yanan Zheng ◽  
Linjuan Sheng ◽  
Hongmei Chen ◽  
Lijuan Zhao ◽  
...  

2017 ◽  
Vol 7 (4) ◽  
pp. 1 ◽  
Author(s):  
Sreedevi Basavaraju ◽  
Chandrasekhar Kathera ◽  
Pramoda Kumari Jasti

The alkaline protease produced by Bacillus cereus UV-15 mutant was purified by precipitation with ammonium sulphate and gel filtration through sephadex G-100. The enzyme has shown to have a molecular weight of 29kDa by SDS polyacrylamide gel electrophoresis. The extracted protease enzyme was purified by 16.64 fold through ammonium sulphate precipitation and chromatography separation in Sephadex G-100. The purified protease had a specific activity of 2915 (U/mg). The zymogram also revealed a clear hydrolytic zone due to proteolytic activity, which coincided with the band obtained with SDS–PAGE. The enzyme was remained active and stable at pH 8-11, with an optimum at pH 10.0. The protease was stable in the temperature ranging from 40°C to 60°C, but gradually decreased at temperature 70°C. The optimum temperature for protease activity was determined at 60°C. The enzyme showed stability towards non-ionic and anionic surfactants, and oxidizing agents. At 1% concentration of Tween-20 and Tween-80, the enzyme retained 78% and 94% relative activity respectively. Alkaline protease retained 95% activity toward 0.5% concentration of the anionic detergent SDS. The enzyme showed compatibility at 50°C with commercial detergents such as Ariel, Surf excel, Rin, wheel, Tide and Nirma. In the presence of Ariel and Rin the enzyme retained about 72 and 75% of the original activity respectively. The supplementation of the enzyme in detergents could improve the cleansing performance towards the blood stains and suggested to be used as a detergent additive. The enzyme also removed goat hide hairs completely after 15 hr of incubation. These characteristics may make the enzyme suitable for several industrial applications, especially in leather industries.


2019 ◽  
Author(s):  
YunFeng Zhang ◽  
Qixing Liang ◽  
Chuanzhi Zhang ◽  
Juan Zhang ◽  
Guocheng Du ◽  
...  

Abstract Background: Trypsin has a plenty application in food and pharmaceutical manufacture. While, the commercial trypsin is usually extracted from pork pancreas, which has the risk of infectious and immunogenicity. Therefore, the microbial Streptomyces griseus trypsin (SGT) is a prior alternation because it processes efficient hydrolysis activity without the aforementioned risk. The remarkable hydrolysis efficiency of SGT caused its autolysis, and five autolysis sites R21, R32, K122, R153, and R201 were identified from its' autolysate. Results: The tbcf (K101A, R201V) mutant was screened by directed selection approach for improved activity in flask culture (60.85 ± 3.42 U·mL -1 , increased 1.5-fold). From the molecular dynamics simulation, the K101A/R201V mutation shortened the distant between catalytical residues D102 and H57 from 6.5 Å vs 7.0 Å, which afforded the improved specific activity 1527.96 ± 62.81 U·mg -1 . Further, the production of trypsin was increased 302.8% (689.47 ± 6.78 U·mL −1 ) in 3-L bio-reactor, with co-overexpression of chaperones SSO2 and UBC1 in Pichia pastoris. Conclusions: The SGT protein could be an adequate trypsin for insulin production. When working with hydrolysates analysis and direction selection, the tbcf (K101A, R201V) mutant increased 1.5-fold activity. Further, the production of trypsin was improved 3-fold by overexpressing chaperone protein in Pichia pastoris . The future study should be emphasized on the application of SGT in insulin manufacture and pharmaceutical.


2018 ◽  
Vol 11 (3) ◽  
pp. 124
Author(s):  
Shella Permatasari Santoso ◽  
Niko Sanjaya ◽  
Aning Ayucitra

The use of cassava peels as raw material for Sodium Carboxymethyl Cellulose productionCassava peels are abundantly available and may be used as an lowcost cellulose source (80-85% cellulose per weight cassava peel). the study was to evaluate the effect of the concentration of sodium hydroxide, sodium chloroacetate, and temperature reaction on the sodium carboxymethyl cellulose (sodium-CMC) characteristics i.e. yield, purity, and degree of substitution in sodium-CMC preparation.  Sodium-CMC functional group was determined using FTIR spectrophotometer. Cassava peels was dried and grounded to 50 mesh. Lignin was eliminated from cassava peel by extraction of grounded cassava peel with 10% NaOH at 35 °C for 5 h. Cassava peel free lignin was then re-extracted using 10% of acetic acid and sodium chloride at 75 °C for 1 h, thus cellulose free hemicellulose was obtained. Alkalization at 30 °C for 90 min was performed by adding sodium hydroxyde at 10-40% to cellulose using isopropyl alcohol solvent. Following this, etherification was conducted by adding sodium chloroacetate of 1-5 g at 50-80 °C for 6 h. As result, the highest purity of sodium-CMC (96.20%) was obtained from alkalization using 20% of sodium hydroxide and etherification using 3 g sodium chloroacetate at 70 °C. Sodium-CMC yield was 22% and degree of substitution 0.705.Keywords: cassava peel, carboxymethyl cellulose, sodium-CMC, etherification AbstrakKulit singkong merupakan sumber selulosa yang berlimpah dan murah, dengan kadar selulosa 80-85% dari berat kulit singkong. Tujuan penelitian ini adalah memanfaatkan selulosa dalam kulit singkong sebagai bahan baku pembuatan natrium karboksimetil selulosa (Na-CMC), mempelajari pengaruh natrium hidroksida, natrium kloroasetat serta suhu pada karakteristik Na-CMC seperti perolehan, kemurnian, dan derajat substitusi, serta menentukan kondisi operasi optimum untuk pembuatan Na-CMC berdasarkan kemurnian Na-CMC terbesar. Gugus fungsi Na-CMC ditentukan menggunakan Fourier Transform Infrared Spectra. Mula-mula, kulit singkong dikeringkan dan dihancurkan sehingga berukuran 50 mesh. Kulit singkong diekstraksi dengan NaOH 10% di suhu 35 °C selama 5 jam, untuk melarutkan lignin. Kulit singkong bebas lignin diekstrak dengan asam asetat 10% dan natrium klorida dengan pemanasan 750 °C selama 1 jam untuk melarutkan hemiselulosa sehingga didapatkan selulosa. Alkalisasi dilakukan dengan mereaksikan selulosa dengan NaOH 10-40% dengan pelarut isopropil alkohol pada suhu 30 °C selama 90 menit, dilanjutkan eterifikasi dengan natrium kloroasetat 1-5 g pada suhu 50-80 °C selama 6 jam. Berdasarkan hasil penelitian, karakteristik Na-CMC terbaik didapatkan dari alkalisasi selulosa menggunakan NaOH 20% serta eterifikasi menggunakan 3 g natrium kloroasetat pada suhu 70 °C. Perolehan Na-CMC yang didapat adalah sebesar 22%, kemurnian 96,20%, derajat substitusi 0,705; termasuk dalam grade kedua menurut SNI 06-3736-1995.Kata kunci: kulit singkong, karboksimetil selulosa, Na-CMC, eterifikasi


2021 ◽  
Vol 12 ◽  
Author(s):  
Jing Si ◽  
Hongfei Ma ◽  
Yongjia Cao ◽  
Baokai Cui ◽  
Yucheng Dai

This study introduces a valuable laccase, designated ThLacc-S, purified from white rot fungus Trametes hirsuta. ThLacc-S is a monomeric protein in nature with a molecular weight of 57.0 kDa and can efficiently metabolize endocrine disrupting chemicals. The enzyme was successfully purified to homogeneity via three consecutive steps consisting of salt precipitation and column chromatography, resulting in a 20.76-fold increase in purity and 46.79% yield, with specific activity of 22.111 U/mg protein. ThLacc-S was deciphered as a novel member of the laccase family and is a rare metalloenzyme that contains cysteine, serine, histidine, and tyrosine residues in its catalytic site, and follows Michaelis-Menten kinetic behavior with a Km and a kcat/Km of 87.466 μM and 1.479 s–1μM–1, respectively. ThLacc-S exerted excellent thermo-alkali stability, since it was markedly active after a 2-h incubation at temperatures ranging from 20 to 70°C and retained more than 50% of its activity after incubation for 72 h in a broad pH range of 5.0–10.0. Enzymatic activities of ThLacc-S were enhanced and preserved when exposed to metallic ions, surfactants, and organic solvents, rendering this novel enzyme of interest as a green catalyst for versatile biotechnological and industrial applications that require these singularities of laccases, particularly biodegradation and bioremediation of environmental pollutants.


2020 ◽  
Vol 5 (3) ◽  
pp. 167
Author(s):  
Safrida Safrida ◽  
Khairil Khairil ◽  
Fani Fardinita

This study determined the antihyperglycemic and antioxidant activity of nanoemulsion extracts of M. affine leaves in alloxan-induced rats. This research used 24 male Wistar rats around three months old which grouped as normal (untreated), negative control (treated with carboxymethyl cellulose sodium/Na-CMC,), positive control (treated with glibenclamide), and various concentration (30, 60, and 90%) of nanoemulsion extract of M. affine leaves groups. The extract of M. affine leaves had an antioxidant activity with IC50 5.30 ppm, categorized as a very strong antioxidant. Furthermore, the administration of this extract decreased glucose levels in antihyperglycemic rats.  We concluded that M. affine leaves extract potential as antioxidants and be developed as an ingredient for diabetic drugs.


2020 ◽  
Author(s):  
Honghai Zhang ◽  
Yuan Wang ◽  
Roman Brunecky ◽  
Bin Yao ◽  
Xiangming Xie ◽  
...  

Abstract Background Swollenins are present in some fungal species involved in the biodegradation of cellulosic substrates. They appear to promote a rearrangement in the network of non-covalent interactions between the cell wall polysaccharides, thus making it more accessible for degradation by hydrolytic enzymes. Here, we have reported a detailed characterization of a recombinant swollenin with respect to its disruptive activity on cellulosic substrates and synergistic effect with cellulases. Results In the present study, a novel swollenin gene Tlswo consisting of an open reading frame encoding 503 amino acids was identified from Talaromyces leycettanus JCM12802 and successfully expressed in Trichoderma reesei and Pichia pastoris. Similar to other fungal swollenins, TlSWO contained a N-terminal family 1 carbohydrate binding module (CBM1) followed by a Ser/Thr rich linker connected to expansin-like domain which includes a family 45 endoglucanase-like domain and group-2 grass pollen allergen domain. TlSWO demonstrated disruptive activity on Avicel and displayed a high synergistic effect with cellobiohydrolases, enhancing its hydrolytic performance up to 132%. The activity of TlSWO on various substrates and biomass was also examined. It was shown that TlSWO could release reducing sugars from lichenan, barley β-glucan, carboxymethyl cellulose sodium (CMC-Na) and laminarin. The specific activity of TlSWO towards the substates above is 9.0 ± 0.100 U/mg, 8.9 ± 0.100U/mg, 2.3 ± 0.002 U/mg and 0.79 ± 0.002 U/mg respectively. Moreover, TlSWO exhibits maximum activity at pH 4.0 and 50 ℃. Conclusion This study reported on a novel swollenin with highly efficient for biomass conversion. It also reveals the functional diversity of swollenin with activity on various substrates. Although the exact mechanism of swollenin catalytic action activity still remains unknown, the functional diversity of TlSWO makes it a good candidate for industrial applications.


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