Journal of Microbiology

Research Support, Non-U.S. Gov't

Characterization and Signature Pattern Analysis of Korean Clade HIV-1 Using nef Gene Sequences: Chan Seung Park , Dong Hun Lee , Keon Myung Lee , Chan-Hee Lee; J. Microbiol. 2008;46(1):88-94.; DOI: https://doi.org/10.1007/s12275-007-0156-x

Abstract: Phylogenetic studies of the HIV-1 gene sequences isolated from Korean patients have suggested that most of Korean isolates belong to the subtype B strain. This study aims to characterize the Korean clade by molecular phylogenetic analysis using all of the Korean nef gene sequences registered in the NCBI GenBank (N=422), in addition to 41 reference strains and 94 foreign isolates. Through phylogenetic analyses, we verified that most of the Korean isolates belonged to the subtype B, where 78.8% are clustered exclusively of foreign isolates. This cluster has been named the Korean clade subtype B (KCB) in order to distinguish it from other subtype B clusters. Genetic distance analysis suggested that the KCB cluster was more homogeneous and clearly distinctive from the non-Korean clade subtype B (NKCB). Comparison of consensus amino acid sequences from KCB and NKCB revealed that characteristic KCB signature amino acid patterns composed of 11 amino acid residues, whose frequencies in the KCB were significantly higher than in the NKCB. The KCB signature amino acid residues were critical in identifying KCB from NKCB, since substitution of the NKCB sequences with KCB signature amino acids relocated them to the Koran clade, and vice versa.

Quantitative analysis of gene expression pattern in aspergillus nidulans mycelia by sequencing of 3'-directed cDNA clones: Park, Yoon Dong , Lee, Dong Whan , Lee, Seog Jae , Kim, Jong Hwa , Chae, Keon Sang; J. Microbiol. 1996;34(1):23-29.

Abstract: Since sequencing of randomly selected cDNA clones has been known to be a powerful approach to obtain information on gene expression pattern in specific cells or tissues, we have analyzed a 3'-directed cDNA library of vegetative mycelia of A. nidulans by single-pass sequencing of hundreds of randomly selected clones. Sequencing of 292 cDNA clones yielded 209 gene signatures (GSs) probably representing highly or lesser expressed genes in the vegetative mycelia. Among the 209 GSs, 25 (79 cDNA clones) appeared more than once and 184 only once. One GS appeared at a highest frequency of 6 times, 2 GSs5 times, 4 GSs 4 times, a GSs 3 times and 16 GSs twice. About 6.6% GSs comprizing of 13 GSs showed alternative polyadenylation. Among 23 redundant GSs, three were common in both mycelia and sexual organs, and 22 were probably mycelia-specific. Out of 209 GSs, 36 were identified in GenBank showing of 70% or greater similaritis. Only six GSs were for A. nidulans genes, and 13 GSs were of DNA or genes encoding cytoplasmic or organellar proteins. This pattern is similar to those in the human HepG2 cell line and in human colonic mucosa, although very few genes for nuclear proteins and for protein synthesis were in A. nidulans.

Quantitative Analysis of Expressed Genes in Aspergillus Oryzae by Sequencing 3'-directed cDNA Clones: Hwang, Hyun Ah , Lee, Dong Whan , Kim, Jong Hwa , Lee, Tae Kyoo , Yang, Moon Sik , Chae, Keon Sang; J. Microbiol. 1998;36(2):111-117.

Abstract: Sequence analysis of randomly selected 3'-directed cKNA clones has been known to be one of the most powerful methods of examining the genes highly expressed in a tissue or cell type. We constructed a 3'-directed cDNA libraty from Aspergillus oryzae mycelia, and sequenced 345 randomly selected 3'-directed cDNA clones. Determined nucleotide sequences, not shorter than 30nt, were compared with one other to generate gene signatures (GSs) and were then compared with GenBank entries to analyze sequence similarity to known genes. A GS for the most highly expressed gene appeared six times, one GS five times, five GSs four times, five GSs three times and 22 GSs twice. In total, 324 clones yielded 268 GSs consisting of 34 redundant GSs appeaning at least twice and 234 solitary ones. Forty-three GSs showed similarities ranging from 60% to 99% with known sequences from Genbank. A considerable number of A. oryzae GSs mateched those obtained from the sexual structures of A. nidulans suggests that A. oryzae may not be phylogentically distant from A. nidulans and that A. oryzae may have a sexual life cycle from the ancient period.

Search