https://repository.kopri.re.kr/handle/201206/13422 2026-04-07T16:02:29Z 2026-04-07T16:02:29Z Kim, Han-Woo https://repository.kopri.re.kr/handle/201206/14762 2023-12-04T02:24:36Z 2023-11-28T00:00:00Z

Title: Development of microbial enzymes degrading recalcitran materials from the Arctic Circle Authors: Kim, Han-Woo

2023-11-28T00:00:00Z Hwang, Jisub Yoo Wanki Shin, Seung Chul Kim Kyeong Kyu Kim Han-Woo Do, Hackwon Lee, Jun Hyuck https://repository.kopri.re.kr/handle/201206/14642 2023-09-25T16:37:35Z 2023-01-01T00:00:00Z

Title: Structural and Biochemical Insights into Bis(2-hydroxyethyl) Terephthalate Degrading Carboxylesterase Isolated from Psychrotrophic Bacterium Exiguobacterium antarcticum Authors: Hwang, Jisub; Yoo Wanki; Shin, Seung Chul; Kim Kyeong Kyu; Kim Han-Woo; Do, Hackwon; Lee, Jun Hyuck Abstract: This study aimed to elucidate the crystal structure and biochemically characterize the carboxylesterase EaEst2, a thermotolerant biocatalyst derived from Exiguobacterium antarcticum, a psychrotrophic bacterium. Sequence and phylogenetic analyses showed that EaEst2 belongs to the Family XIII group of carboxylesterases. EaEst2 has a broad range of substrate specificities for short-chain p-nitrophenyl (pNP) esters, 1-naphthyl acetate (1-NA), and 1-naphthyl butyrate (1-NB). Its optimal pH is 7.0, losing its enzymatic activity at temperatures above 50 & DEG;C. EaEst2 showed degradation activity toward bis(2-hydroxyethyl) terephthalate (BHET), a polyethylene terephthalate degradation intermediate. We determined the crystal structure of EaEst2 at a 1.74 & ANGS; resolution in the ligand-free form to investigate BHET degradation at a molecular level. Finally, the biochemical stability and immobilization of a crosslinked enzyme aggregate (CLEA) were assessed to examine its potential for industrial application. Overall, the structural and biochemical characterization of EaEst2 demonstrates its industrial potency as a biocatalyst.

2023-01-01T00:00:00Z 윤혜리 구단열 한석 Shin, Seung Chul Kim, Han-Woo 김효진 https://repository.kopri.re.kr/handle/201206/14086 2022-11-21T16:36:59Z 2022-01-01T00:00:00Z

Title: Safety evaluation of mycotoxin citrinin production from Monascus ruber through whole-genome sequencing and analytical evaluation Authors: 윤혜리; 구단열; 한석; Shin, Seung Chul; Kim, Han-Woo; 김효진 Abstract: In this study, the whole genome of Monascus ruber KACC 46666 was generated using the PacBio RSII sequencer with high-quality de novo assembly to obtain trustworthy assembly and annotation using genome assemblies with long reads from PacBio single-molecule real-time sequencing. The whole genome of M. ruber has a total length of 25.9 Mb, divided in 13 contigs with 9639 genes. The functions of genes involved in secondary metabolite production were further analyzed. Gene clusters involved in the production of Monascus pigment, monacolin K, and mycotoxin citrinin were identified. Notably, most of the citrinin gene cluster was lost, as confirmed via high-performance liquid chromatography analysis. This genome-level safety evaluation of industrially important Monascus strains will provide valuable information for genome-based microbial engineering of natural food colorants and production of commercially important secondary metabolites such as monacolin K.

2022-01-01T00:00:00Z Ly Thi Huong Luu Le 유완기 Ying Wang 전상근 김경규 Kim, Han-Woo 김두헌 https://repository.kopri.re.kr/handle/201206/14087 2022-11-21T16:37:00Z 2022-01-01T00:00:00Z

Title: Dual functional roles of a novel bifunctional β-lactamase/esterase from Lactococcus garvieae Authors: Ly Thi Huong Luu Le; 유완기; Ying Wang; 전상근; 김경규; Kim, Han-Woo; 김두헌 Abstract: A novel bifunctional β-lactamase/esterase (LgLacI), which is capable of hydrolyzing β-lactam-containing antibiotics including ampicillin, oxacillin, and cefotaxime as well as synthesizing biodiesels, was cloned from Lactococcus garvieae. Unlike most bacterial esterases/lipases that have G-x-S-x-G motif, LgLacI, which contains S-x-x- K catalytic motif, has sequence similarities to bacterial family VIII esterase as well as β-lactamases. The catalytic properties of LgLacI were explored using a wide range of biochemical methods including spectroscopy, assays, structural modeling, mutagenesis, and chromatography. We confirmed the bifunctional property of LgLacI hydrolyzing both esters and β-lactam antibiotics. This study provides novel perspectives into a bifunctional enzyme from L. garvieae, which can degrade β-lactam antibiotics with high esterase activity.

2022-01-01T00:00:00Z