Scholarlink

<p>Salinity stress represents a critical threat to global agricultural productivity and food security, necessitating innovative approaches to enhance crop tolerance mechanisms. Glycine betaine (GB) is a key compatible solute in osmoadaptation, and its biosynthesis is mediated by the genes <i>gbsA</i> and <i>gbsB</i>. Codon usage was compared for <i>gbsA</i> and <i>gbsB</i> across 84 eubacterial species spanning five taxonomic classes, and assessed alongside the housekeeping gene <i>rpoB</i>. Across the dataset, codon-bias metrics converged on a predominant role for translational selection in shaping synonymous codon choice, with mutational pressure contributing less. Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria and Actinomycetes generally favored GC-ending codons in both <i>gbsA</i> and <i>gbsB</i>. Bacilli, however, showed a divergent regime in which third-position nucleotide composition was strongly AT-biased, preferred codons often differed from those in GC-biased groups, and the usual coupling between GC3 and codon-bias strength was weak or absent for <i>gbsA</i> and <i>gbsB</i>. Analyses of the 5′, middle and 3′ coding regions did not indicate meaningful positional shifts in codon usage, suggesting broadly uniform constraints along each gene. Estimates of dN/dS below 1 for <i>gbsA</i> and <i>gbsB</i> support pervasive purifying selection, consistent with functional conservation of GB biosynthetic enzymes. These findings provide crucial insights for the rational design of heterologous expression systems and the strategic optimization of transgene expression in plant engineering. They also establish a foundation for evidence-based genetic engineering strategies to enhance agricultural resilience against salinity stress.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Glycine betaine biosynthesis genes conferring osmotic tolerance in eubacteria depict the predominant role of translational selection in shaping the codon usage pattern

  • 期刊论文

  • 发表日期：

    2026年7月14日

查看全文
  • Madhumita G. Chaki,
  • Vivek Roy,
  • Ayon Pal

摘要

Salinity stress represents a critical threat to global agricultural productivity and food security, necessitating innovative approaches to enhance crop tolerance mechanisms. Glycine betaine (GB) is a key compatible solute in osmoadaptation, and its biosynthesis is mediated by the genes gbsA and gbsB. Codon usage was compared for gbsA and gbsB across 84 eubacterial species spanning five taxonomic classes, and assessed alongside the housekeeping gene rpoB. Across the dataset, codon-bias metrics converged on a predominant role for translational selection in shaping synonymous codon choice, with mutational pressure contributing less. Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria and Actinomycetes generally favored GC-ending codons in both gbsA and gbsB. Bacilli, however, showed a divergent regime in which third-position nucleotide composition was strongly AT-biased, preferred codons often differed from those in GC-biased groups, and the usual coupling between GC3 and codon-bias strength was weak or absent for gbsA and gbsB. Analyses of the 5′, middle and 3′ coding regions did not indicate meaningful positional shifts in codon usage, suggesting broadly uniform constraints along each gene. Estimates of dN/dS below 1 for gbsA and gbsB support pervasive purifying selection, consistent with functional conservation of GB biosynthetic enzymes. These findings provide crucial insights for the rational design of heterologous expression systems and the strategic optimization of transgene expression in plant engineering. They also establish a foundation for evidence-based genetic engineering strategies to enhance agricultural resilience against salinity stress.