Search | Engineering

Subscribe Submit

Home Journals Focus Achievement Fronts About Us 中文版

Resource Type

Journal Article 2

Year

2023 1

2014 1

Keywords

Halomonas bluephagenesis 1

α-acetolactate decarboxylase 1

α-acetolactate synthetase 1

β-glucuronidase encapsulation 1

acetoin 1

biocatalysis 1

biomimetic synthesis 1

pyruvate 1

silica nanoparticles 1

storage and recycling stability 1

whole-cell biocatalysis 1

open ︾

Search scope:

排序： Display mode:

Efficient acetoin production from pyruvate by engineered whole-cell biocatalysis

Frontiers of Chemical Science and Engineering 2023, Volume 17, Issue 4, Pages 425-436 doi: 10.1007/s11705-022-2229-0

Abstract: Acetoin is an important platform chemical, which has a wide range of applications in many industries. Halomonas bluephagenesis, a chassis for next generation of industrial biotechnology, has advantages of fast growth and high tolerance to organic acid salts and alkaline environment. Here, α-acetolactate synthase and α-acetolactate decarboxylase from Bacillus subtilis 168 were co-expressed in H. bluephagenesis to produce acetoin from pyruvate. After reaction condition optimization and further increase of α-acetolactate decarboxylase expression, acetoin production and yield were significantly enhanced to 223.4 mmol·L^–1 and 0.491 mol·mol^–1 from 125.4 mmol·L^–1 and 0.333 mol·mol^–1, respectively. Finally, the highest titer of 974.3 mmol·L^–1 (85.84 g·L^–1) of acetoin was accumulated from 2143.4 mmol·L^–1 (188.6 g·L^–1) of pyruvic acid within 8 h in fed-batch bioconversion under optimal reaction conditions. Moreover, the reusability of the cell catalysis was also tested, and the result illustrated that the whole-cell catalysis obtained 433.3, 440.2, 379.0, 442.8 and 339.4 mmol·L^–1 (38.2, 38.8, 33.4, 39.0 and 29.9 g·L^–1) acetoin in five repeated cycles under the same conditions. This work therefore provided an efficient H. bluephagenesis whole-cell catalysis with a broad development prospect in biosynthesis of acetoin.

Keywords： acetolactate synthetase α-acetolactate decarboxylase Halomonas bluephagenesis whole-cell biocatalysis

HTML PDF Collect

Immobilization of

Xiaokai SONG,Zhongyi JIANG,Lin LI,Hong WU

Frontiers of Chemical Science and Engineering 2014, Volume 8, Issue 3, Pages 353-361 doi: 10.1007/s11705-014-1421-2

Abstract: Mesoporous silica particles were prepared for efficient immobilization of the -glucuronidase (GUS) through a biomimetic mineralization process, in which the solution containing lysozyme and GUS were added into the prehydrolyzed tetraethoxysilane (TEOS) solution. The silica particles were formed in a way of biomineralization under the catalysis of lysozyme and GUS was immobilized into the silica particles simultaneously during the precipitation process. The average diameter of the silica particles is about 200 nm with a pore size of about 4 nm. All the enzyme molecules are tightly entrapped inside the biosilica nanoparticles without any leaching even under a high ionic strength condition. The immobilized GUS exhibits significantly higher thermal and pH stability as well as the storage and recycling stability compared with GUS in free form. No loss in the enzyme activity of the immobilized GUS was found after 30-day’s storage, and the initial activity could be well retained after 12 repeated cycles.

Keywords： storage and recycling stability silica nanoparticles biocatalysis biomimetic synthesis β-glucuronidase