West African Centre for Cell Biology of Infectious Pathogens (WACCBIP)/Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana.
Department of Medical Laboratory Sciences, University of Ghana, Korle Bu, Accra, Ghana.
Biomed Res Int. 2021 Mar 30;2021:6616059. doi: 10.1155/2021/6616059. eCollection 2021.
pathogenicity and disease severity are determined by the tyrosine phosphorylation motifs of CagA protein. This study is aimed at detecting the presence of . and identifying the CagA tyrosine phosphorylation motifs in Ghanaian patients. . A total of 94 archival genomic DNA samples from gastric biopsies were used for the study, and . was detected by amplifying the 16S rRNA gene. The 3'-end variable region of the cagA gene was amplified, and the entire 3'-end was sequenced and translated into amino acids.
. was detected in 53.2% (50/94) of the samples, and all the detected bacteria harboured the gene. Two variants of the bacteria were identified based on the size of the amplified gene: 207 bp and 285 bp. The 207 bp and 285 bp variants accounted for 74% and 22%, respectively, and 4% showed both fragments. Translated amino acid sequence of the gene showed EPIYA-A, EPIYA-B, and EPIYA-C (ABC type) motifs, indicating the Western variant. The CagA protein C-terminal showed insertion of amino acids in the sequence flanking the EPIYA-A motif at the N-terminal and a complete deletion of the EPIYA-CC and EPIYA-CCC motifs together with the flanking sequences.
. identified were Western variant (ABC type) with unique amino acid insertions, suggesting unique variants in Ghanaian patients. Further investigation is however required to understand the role of the molecular diversity of the variant in gastric disease outcome.
CagA 蛋白的酪氨酸磷酸化基序决定了其致病性和疾病严重程度。本研究旨在检测加纳患者中. 的存在并鉴定 CagA 酪氨酸磷酸化基序。使用 94 个来自胃活检的存档基因组 DNA 样本进行研究，通过扩增 16S rRNA 基因来检测. 。扩增 cagA 基因的 3'-末端可变区，并对整个 3'-末端进行测序并翻译成氨基酸。
在 53.2%（50/94）的样本中检测到. ，所有检测到的细菌均携带 基因。根据扩增基因的大小鉴定出两种细菌变异体：207bp 和 285bp。207bp 和 285bp 变异体分别占 74%和 22%，4%的样本同时显示两种片段。基因翻译的氨基酸序列显示 EPIYA-A、EPIYA-B 和 EPIYA-C（ABC 型）基序，表明为西方变异体。CagA 蛋白 C 末端在 N 端的 EPIYA-A 基序侧翼序列中插入了氨基酸，并且完整缺失了 EPIYA-CC 和 EPIYA-CCC 基序以及侧翼序列。
鉴定出的. 为西方变异体（ABC 型），具有独特的氨基酸插入，提示加纳患者存在独特的变异体。然而，需要进一步研究以了解变异体的分子多样性在胃疾病结局中的作用。
