Scholarlink

<p>Dioxin contamination represents a serious global environmental threat, particularly in developing and climate-vulnerable regions. This study evaluates the potential of <i>Bacillus velezensis</i> Bm3, isolated from a dioxin-contaminated site in central Syria, for the aerobic biodegradation of 2,3,7,8-tetrachlorodibenzo-<i>p</i>-dioxin (TCDD). Quantitative analyses demonstrated a strong biodegradative capacity, with 71% and 76% of the initial TCDD concentration removed after 5 and 6&#xa0;weeks, respectively. Whole-genome sequencing revealed a 5.29 Mbp genome encoding 5411 predicted proteins, providing a solid genetic basis for this activity. A two-step degradation pathway is proposed, initiated by cytochrome P450-mediated hydroxylation of TCDD to dihydroxy-hydrodibenzo-<i>p</i>-dioxin, followed by conversion to the key intermediate catechol. This compound is subsequently cleaved by catechol 2,3-dioxygenase, yielding acetaldehyde and pyruvate. Gene expression and protein accumulation analyses supported this mechanism, showing strong induction of a specific cytochrome P450 isoform (CYPBM3_v1_ua3131) and cat-2,3-diox transcripts. These findings identify <i>B. velezensis</i> Bm3 as a promising candidate for TCDD bioremediation in warm, dry environments.</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

Genome-based analysis of Bacillus velezensis Bm3 isolated from a vulnerable dioxin-contaminated site in central Syria reveals mechanisms of dioxin degradation

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年4月29日

查看全文
  • Sabrin Mahfouz,
  • Sylvie Nazaret,
  • Agnès Richaume,
  • Abdulsamie Hanano

摘要

Dioxin contamination represents a serious global environmental threat, particularly in developing and climate-vulnerable regions. This study evaluates the potential of Bacillus velezensis Bm3, isolated from a dioxin-contaminated site in central Syria, for the aerobic biodegradation of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Quantitative analyses demonstrated a strong biodegradative capacity, with 71% and 76% of the initial TCDD concentration removed after 5 and 6 weeks, respectively. Whole-genome sequencing revealed a 5.29 Mbp genome encoding 5411 predicted proteins, providing a solid genetic basis for this activity. A two-step degradation pathway is proposed, initiated by cytochrome P450-mediated hydroxylation of TCDD to dihydroxy-hydrodibenzo-p-dioxin, followed by conversion to the key intermediate catechol. This compound is subsequently cleaved by catechol 2,3-dioxygenase, yielding acetaldehyde and pyruvate. Gene expression and protein accumulation analyses supported this mechanism, showing strong induction of a specific cytochrome P450 isoform (CYPBM3_v1_ua3131) and cat-2,3-diox transcripts. These findings identify B. velezensis Bm3 as a promising candidate for TCDD bioremediation in warm, dry environments.