Journal of Microbiology

Journal Articles

Transposon insertion site sequencing (TIS) of Pseudomonas aeruginosa: Hongbaek Cho; J. Microbiol. 2021;59(12):1067-1074. Published online December 4, 2021; DOI: https://doi.org/10.1007/s12275-021-1565-y

Abstract: Transposon insertion site sequencing (TIS) is a technique that determines the insertion profile of a transposon mutant library by massive parallel sequencing of transposon-genomic DNA junctions. Because the transposon insertion profile reflects the abundance of each mutant in the library, it provides information to assess the fitness contribution of each genetic locus of a bacterial genome in a specific growth condition or strain background. Although introduced only about a dozen years ago, TIS has become an important tool in bacterial genetics that provides clues to study biological functions and regulatory mechanisms. Here, I describe a protocol for generating high density transposon insertion mutant libraries and preparing Illumina sequencing samples for mapping the transposon junctions of the transposon mutant libraries using Pseudomonas aeruginosa as an example.

Isolation of a novel strain, Sphingorhabdus sp. YGSMI21 and characterization of its enantioselective epoxide hydrolase activity: Jung-Hee Woo , Hae-Seon Kim , Nyun-Ho Park , Ho Young Suk; J. Microbiol. 2021;59(7):675-680. Published online June 1, 2021; DOI: https://doi.org/10.1007/s12275-021-1023-x

Abstract: Sphingorhabdus sp. YGSMI21, a novel microbial strain with an enantioselective epoxide hydrolase activity, was isolated from tidal samples contaminated by accidental oil spills subjected to enriched culture with polycyclic aromatic hydrocarbon. This strain was able to optically decompose (R)-styrene oxide (SO) and showed 100% optical purity. In addition, it showed a good enantioselectivity for the derivatives of (S)- SO, (S)-2-chlorostyrene oxide (CSO), (S)-3-CSO and (S)-4- CSO. For (S)-2-CSO, (S)-3-CSO and (S)-4-CSO, 99.9%ee was obtained with the yield of 26.2%, 24.8%, and 11.0%, respectively, when using 10 mg cells of Sphingorhabdus sp. YGSMI21 at pH 8.0 with 4 mM racemic substrates at pH 8.0 and 25°C. The values obtained in this study for (S)-2-CSO, particularly the yield of 26.2%, is noteworthy, considering that obtaining an enantiomerically pure form is difficult. Taken together, Sphingorhabdus sp. YGSMI21 can be regarded as a wholecell biocatalyst in the production of various (S)-CSO with the chlorine group at a different position.

Search