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Chen X.-L.,Fujian Agriculture and forestry University | Chen X.-L.,State Oceanic Administration | Hou Y.-P.,State Oceanic Administration | Jin M.,State Oceanic Administration | And 4 more authors.
Journal of Agricultural and Food Chemistry | Year: 2016

A novel gene (aga4436), encoding a potential agarase of 456 amino acids, was identified in the genome of deep-sea bacterium Flammeovirga sp. OC4. Aga4436 belongs to the glycoside hydrolase 16 β-agarase family. Aga4436 was expressed in Escherichia coli as a fusion protein and purified. Recombinant Aga4436 showed an optimum agarase activity at 50-55 °C and pH 6.5, with a wide active range of temperatures (30-80 °C) and pHs (5.0-10.0). Notably, Aga4436 retained more than 90%, 80%, and 35% of its maximum activity after incubation at 30 °C, 40 °C, and 50 °C for 144 h, respectively, which exhibited an excellent thermostability in medium-high temperatures. Besides, Aga4436 displayed a remarkable tolerance to acid and alkaline environments, as it retained more than 70% of its maximum activity at a wide range of pHs from 3.0 to 10.0 after incubation in tested pHs for 60 min. These desirable properties of Aga4436 could make Aga4436 attractive in the food and nutraceutical industries. © 2016 American Chemical Society.


Wang Y.,CAS South China Sea Institute of Oceanology | Wang Y.,University of Chinese Academy of Sciences | Zhang Y.,CAS South China Sea Institute of Oceanology | Hu Y.,CAS South China Sea Institute of Oceanology | Hu Y.,South China Sea Bio Resource Exploitation and Utilization Collaborative Innovation Center
Applied Biochemistry and Biotechnology | Year: 2016

One novel microbial esterase PHE21 was cloned from the genome of Pseudomonas oryzihabitans HUP022 identified from the deep sea of the Western Pacific. PHE21 was heterologously expressed and functionally characterized to be a robust esterase which behaved high resistance to various metal ions, organic solvents, surfactants, and NaCl. Despite the fact that the two enantiomers of ethyl 3-hydroxybutyrate were hard to be enzymatically resolved before, we successfully resolved racemic ethyl 3-hydroxybutyrate through direct hydrolysis reactions and generated chiral ethyl (S)-3-hydroxybutyrate using esterase PHE21. After process optimization, the enantiomeric excess, the conversion rate, and the yield of desired product ethyl (S)-3-hydroxybutyrate could reach 99, 65, and 87 %, respectively. PHE21 is a novel marine microbial esterase with great potential in asymmetric synthesis as well as in other industries. © 2016 Springer Science+Business Media New York


Tong Y.,CAS South China Sea Institute of Oceanology | Tong Y.,South China Sea Bio Resource Exploitation and Utilization Collaborative Innovation Center | Zhang Y.,CAS South China Sea Institute of Oceanology | Zhang Y.,South China Sea Bio Resource Exploitation and Utilization Collaborative Innovation Center | And 9 more authors.
PLoS ONE | Year: 2015

Background The reproductive mechanisms of mollusk species have been interesting targets in biological research because of the diverse reproductive strategies observed in this phylum. These species have also been studied for the development of fishery technologies in molluscan aquaculture. Although the molecular mechanisms underlying the reproductive process have been well studied in animal models, the relevant information from mollusks remains limited, particularly in species of great commercial interest. Crassostrea hongkongensis is the dominant oyster species that is distributed along the coast of the South China Sea and little genomic information on this species is available. Currently, high-throughput sequencing techniques have been widely used for investigating the basis of physiological processes and facilitating the establishment of adequate genetic selection programs. Results The C.hongkongensis transcriptome included a total of 1,595,855 reads, which were generated by 454 sequencing and were assembled into 41,472 contigs using de novo methods. Contigs were clustered into 33,920 isotigs and further grouped into 22,829 isogroups. Approximately 77.6% of the isogroups were successfully annotated by the Nr database. More than 1,910 genes were identified as being related to reproduction. Some key genes involved in germline development, sex determination and differentiation were identified for the first time in C.hongkongensis (nanos, piwi, ATRX, FoxL2, β-catenin, etc.). Gene expression analysis indicated that vasa, nanos, piwi, ATRX, FoxL2, β-catenin and SRD5A1 were highly or specifically expressed in C.hongkongensis gonads. Additionally, 94,056 single nucleotide polymorphisms (SNPs) and 1,699 simple sequence repeats (SSRs) were compiled. Conclusions Our study significantly increased C.hongkongensis genomic information based on transcriptomics analysis. The group of reproduction-related genes identified in the present study constitutes a new tool for research on bivalve reproduction processes. The large group of molecular markers discovered in this study will be useful for population screening and marker assisted selection programs in C.hongkongensis aquaculture. Copyright: © 2015 Tong et al.


Wang Y.,CAS South China Sea Institute of Oceanology | Wang Y.,University of Chinese Academy of Sciences | Zhang Y.,CAS South China Sea Institute of Oceanology | Sun A.,CAS South China Sea Institute of Oceanology | And 2 more authors.
Cuihua Xuebao/Chinese Journal of Catalysis | Year: 2016

A novel marine microbial esterase PHE14 was cloned from the genome of Pseudomonas oryzihabitans HUP022 isolated from the deep sea of the western Pacific Ocean. Esterase PHE14 exhibited very good tolerance to most organic solvents, surfactants and metal ions tested, thus making it a good esterase candidate for organic synthesis that requires an organic solvent, surfactants or metal ions. Esterase PHE14 was utilized as a biocatalyst in the asymmetric synthesis of D-methyl lactate by enzymatic kinetic resolution. D-methyl lactate is a key chiral chemical. Contrary to some previous reports, the addition of an organic solvent and surfactants in the enzymatic reaction did not have a beneficial effect on the kinetic resolution catalyzed by esterase PHE14. Our study is the first report on the preparation of the enantiomerically enriched product D-methyl lactate by enzymatic kinetic resolution. The desired enantiomerically enriched product D-methyl lactate was obtained with a high enantiomeric excess of 99% and yield of 88.7% after process optimization. The deep sea microbial esterase PHE14 is a green biocatalyst with very good potential in asymmetric synthesis in industry and can replace the traditional organic synthesis that causes pollution to the environment. © 2016, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.


Liang J.,CAS South China Sea Institute of Oceanology | Zhang Y.,CAS South China Sea Institute of Oceanology | Sun A.,CAS South China Sea Institute of Oceanology | Deng D.,CAS South China Sea Institute of Oceanology | And 2 more authors.
Applied Biochemistry and Biotechnology | Year: 2016

A novel microbial esterase BSE01281 identified from the Indian Ocean was cloned, expressed, and functionally characterized. Esterase BSE01281 could enanoselectively resolve (±)-1-phenylethanol and (±)-1-phenylethyl acetate through two types of enzymatic reactions. After the optimization of enzymatic reactions, BSE01281 could efficiently generate (R)-1-phenylethyl acetate with high enantiomeric excess (>99 %) and high conversion (42 %) after 96 h trans-esterification reactions. Additionally, BSE01281 could also produce (R)-1-phenylethanol (e.e. > 99 %) and (S)-1-phenylethyl acetate (e.e. > 95 %) at a conversion of 49 % through direct hydrolysis of inexpensive racemic 1-phenylethyl acetate for 8 h. Optically pure (R)-1-phenylethanol generated from direct enzymatic hydrolysis of racemic 1-phenylethyl acetate by BSE01281 is not easily prepared by dehydrogenases, which generally follow the “Prelog’s rule” and give (S)-1-phenylethanol instead. © 2015, Springer Science+Business Media New York.


Deng D.,CAS South China Sea Institute of Oceanology | Deng D.,University of Chinese Academy of Sciences | Zhang Y.,CAS South China Sea Institute of Oceanology | Sun A.,CAS South China Sea Institute of Oceanology | And 2 more authors.
Applied Biochemistry and Biotechnology | Year: 2016

One novel esterase DAEst6 was identified from the genome of Dactylosporangium aurantiacum subsp. Hamdenensis NRRL 18085. DAEst6 was further characterized to be an esterase which exhibited high resistance to high pH values. Esterase DAEst6 could resolve racemic methyl mandelate and generate (R)-methyl mandelate, one key drug intermediate, with an enantiomeric excess and a conversion of 99 and 49 %, respectively, after process optimization. The optimal working condition for the preparation of (R)-methyl mandelate through DAEst6 was found to be 10-mM racemic methyl mandelate, no organic co-solvents, pH 7.5, and 40 °C, for 5 h. Our work was the first report about the functional characterization of one novel Dactylosporangium esterase and the utilization of one Dactylosporangium esterase in kinetic resolution. Dactylosporangium esterases represented by DAEst6 possess great potential in the generation of valuable chiral drug intermediates and chemicals. © 2016, Springer Science+Business Media New York.


Huang J.,CAS South China Sea Institute of Oceanology | Huang J.,University of Chinese Academy of Sciences | Zhang Y.,CAS South China Sea Institute of Oceanology | Hu Y.,CAS South China Sea Institute of Oceanology | Hu Y.,South China Sea Bio Resource Exploitation and Utilization Collaborative Innovation Center
Applied Biochemistry and Biotechnology | Year: 2016

Chiral lactic acid and its ester derivatives are crucial building blocks and platforms in the generation of high value-added drugs, fine chemicals and functional materials. Optically pure D-lactic acid and its ester derivatives cannot be directly generated from fermentation and are quite expensive. Herein, we identified, heterologously expressed and functionally characterized one Bacillus esterase BSE01701 from the deep sea of the Indian Ocean. Esterase BSE01701 could enzymatically resolve inexpensive racemic methyl lactate and generate chiral D-methyl lactate. The enantiomeric excess of desired chiral D-methyl lactate and the substrate conversion could reach over 99 % and 60 %, respectively, after process optimization. Notably, the addition of 60 % (v/v) organic co-solvent heptane could greatly improve both the enantiomeric excess of D-methyl lactate and the conversion. BSE01701 was a very promising marine microbial esterase in the generation of chiral chemicals in industry. © 2016 Springer Science+Business Media New York


Liu J.,CAS South China Sea Institute of Oceanology | Jung J.H.,Pusan National University | Liu Y.,CAS South China Sea Institute of Oceanology | Liu Y.,South China Sea Bio Resource Exploitation and Utilization Collaborative Innovation Center
Current Medicinal Chemistry | Year: 2016

It is known that marine invertebrates, including sponges, tunicates, cnidaria or mollusks, host affluent and various communities of symbiotic microorganisms. The microorganisms associated with the invertebrates metabolized various biologically active compounds, which could be an important resource for the discovery and development of potentially novel drugs. In this review, the new compounds with antimicrobial activity isolated from marine invertebrate-derived microorganisms in the last decade (2004-2014) will be presented, with focus on the relevant antimicrobial activities, origin of isolation, and information of strain species. New compounds without antimicrobial activity were not revealed. © 2016 Bentham Science Publishers.


Chan Z.,Third Institute of Oceanography | Zhong T.,Third Institute of Oceanography | Yi Z.,Third Institute of Oceanography | Xiao J.,Third Institute of Oceanography | Zeng R.,South China Sea Bio Resource Exploitation and Utilization Collaborative Innovation Center
Biotechnology and Bioprocess Engineering | Year: 2015

The aim of this work is to enhance enduracidin production by Streptomyces sp. MC079. Based on the time course analysis of the specific cell growth rate and specific enduracidin formation rate, a two–stage pH control strategy was proposed to improve enduracidin production by shifting the culture pH from 5.5 to 5.8 after 112 h of cultivation. By applying this pH control strategy, enduracidin concentration and productivity was 51.2 and 65.0% higher than results with uncontrolled pH batch fermentation. For further enhancement of enduracidin production, the effects of constant–rate feeding and pH-shift feeding strategy were investigated. The results indicated that the pH-shift feeding strategy increased the maximum concentration and productivity of enduracidin to 61.37 mg/L and 0.697 mg/L/h in the constant–rate feeding fermentation process. This is 73.3 and 88.9% higher than results with uncontrolled pH batch fermentation, respectively. The obtained optimal pH shift feeding strategy may be useful for the industrial–scale microbial production of enduracidin. © 2015, The Korean Society for Biotechnology and Bioengineering and Springer-Verlag Berlin Heidelberg.


Chan Z.,Third Institute of Oceanography | Wang R.,Third Institute of Oceanography | Yang F.,Third Institute of Oceanography | Zeng R.,Third Institute of Oceanography | Zeng R.,South China Sea Bio Resource Exploitation and Utilization Collaborative Innovation Center
Chinese Journal of Chemical Engineering | Year: 2016

A metagenomic library recombinant clone CAPL3, an Escherichia coli strain generated by transformed with metagenomic library from deep-sea sediments, can efficiently produce cold active lipase. The effects of both temperature and dissolved oxygen (DO) on cold active lipase production by batch culture of metagenomic library recombinant clone (CAPL3) from deep-sea sediment were investigated. First, a two-stage temperature control strategy was developed, in which the temperature was kept at 34 °C for the first 15 h, and then switched to 30 °C. The cold active lipase activity and productivity reached 315.2 U·ml− 1 and 8.08 U·ml− 1·h− 1, respectively, increased by both 14.5% compared to the results obtained with temperature controlled at 30°C. In addition, different DO control modes were conducted, based on the data obtained from the different DO control strategies and analysis of kinetics parameters at different DO levels. A step-wise temperature and DO control strategy were developed to improve lipase production, i.e., temperature and DO level were controlled at 34 °C, 30% during 0–15 h; 30 °C, 30% during 15–18 h, and 30 °C, 20% during 18–39 h. With this strategy, the maximum lipase activity reached 354.6 U·ml− 1 at 39 h, which was 28.8% higher than that achieved without temperature and DO control (275.3 U·ml− 1). © 2016

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