Journal of Microbiology

Journal Articles

Heterologous Production and Structure Determination of a New Lanthipeptide Sinosporapeptin Using a Cryptic Gene Cluster in an Actinobacterium Sinosporangium siamense: Keita Saito , Keiichiro Mukai , Issara Kaweewan , Hiroyuki Nakagawa , Takeshi Hosaka , Shinya Kodani; J. Microbiol. 2023;61(6):641-648. Published online June 12, 2023; DOI: https://doi.org/10.1007/s12275-023-00059-z

Abstract: Lipolanthine is a subclass of lanthipeptide that has the modification of lipid moiety at the N-terminus. A cryptic biosynthetic gene cluster comprising four genes (sinA, sinKC, sinD, and sinE) involved in the biosynthesis of lipolanthine was identified in the genome of an actinobacterium Sinosporangium siamense. Heterologous coexpression of a precursor peptide coding gene sinA and lanthipeptide synthetase coding gene sinKC in the host Escherichia coli strain BL21(DE3) resulted in the synthesis of a new lanthipeptide, sinosporapeptin. It contained unusual amino acids, including one labionin and two dehydrobutyrine residues, as determined using NMR and MS analyses. Another coexpression experiment with two additional genes of decarboxylase (sinD) and N-acetyl transferase (sinE) resulted in the production of a lipolanthine-like modified sinosporapeptin.

Increase in the genetic polymorphism of varicella-zoster virus after passaging in in vitro cell culture: Hye Rim Hwang , Seok Cheon Kim , Se Hwan Kang , Chan Hee Lee; J. Microbiol. 2019;57(11):1033-1039. Published online October 28, 2019; DOI: https://doi.org/10.1007/s12275-019-9429-4

Abstract: Primary infections with the varicella-zoster virus (VZV) result in varicella, while latent reactivation leads to herpes zoster. Both varicella and zoster can be prevented by live attenuated vaccines. There have been reports suggesting that both clinical VZV strains and those in vaccine preparations are genetically polymorphic, containing mixtures of both wild-type and vaccine-type sequences at certain vaccine-specific sites. In this study, the genetic polymorphism of the VZV genome was examined by analyzing the frequencies of minor alleles at each nucleotide position. Next-generation sequencing of the clinical VZV strain YC02 passaged in an in vitro cell culture was used to identify genetically polymorphic sites (GPS), where the minor allele frequency (MAF) exceeded 5%. The number of GPS increased by 7.3-fold at high passages (p100) when compared to low passages (p17), although the average MAF remained similar. GPS were found in 6 open reading frames (ORFs) in p17, 35, and 54 ORFs in p60 and p100, respectively. GPS were found more frequently in the dispensable gene group than the essential gene group, but the average MAF was greater in the essential gene group. The most common two major/minor base pairs were A/g and T/c. GPS were found in all three passages at 16 positions, all located in the reiterated (R) region. The population diversity as measured by Shannon entropy increased in p60 and p100. However, the entropy remained unchanged in the R regions.

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