Daily Archives: 2025年12月15日

Phyloseq objects used in the workflow (ps_*)

!!!!! Good candidate for the workshop for the clinicians !!!!!

ps_* object What it contains Taxonomic composition Alpha diversity Beta diversity DESeq2 differential abundance
ps_raw Raw imported phyloseq object (integer counts; as imported) ❌ (not recommended directly) ⚠️ only if you also apply sample filtering first
ps_base ps_raw + taxonomy + sample metadata aligned (still raw counts) ⚠️ only if you also apply sample filtering first
ps_pruned Optional subset of ps_base (e.g., remove unwanted samples by ID/pattern); still raw counts ⚠️ only if you also apply low-depth filtering
ps_filt Filtered samples (low-depth samples removed) + taxa with nonzero totals; absolute counts ✅ as a starting point (but plot on ps_rel) ✅ as the input to rarefaction ✅ as the input to rarefaction ✅ as the input to ps_deseq
ps_rel Relative abundance (compositional) computed from ps_filt ✅ primary
ps_abund Absolute counts after “plotting taxa filter” (e.g., mean rel. abundance > 0.1%), derived from ps_filt via ps_rel ✅ (if you want cleaner plots) ❌ (not recommended)
ps_abund_rel Relative abundance computed from ps_abund (filtered taxa set) ✅ (clean composition plots)
ps_rarefied Rarefied counts from ps_filt (even depth) ✅ primary ✅ primary
ps_deseq Non-rarefied integer counts from ps_filt + optional count-based taxon prefilter (e.g., total ≥ 10) ✅ primary

Why the ΔadeIJ Evidence Chain Is Not Fully “Closed”

efflux_logica_table

这里说“证据链没有闭环”,不是否定结果,而是从审稿人最严格的因果标准来看,ΔadeIJ 这条线目前更像“相关性很强 + 合理推断”,但还缺少几步能把“推断”锁死成“因果”的关键证据。

1) 目前已有的证据(强相关)

  • 表型:ΔadeIJ 的 ROS 更高,对 Cu²⁺ / SNP 更敏感
  • 转录组:ΔadeIJ 上调金属外排/解毒/应激相关基因

因此很自然会推断:

AdeIJ 参与金属/氧化应激稳态(redox & metal homeostasis)

这属于 “一致性证据(consistent with)”,说服力已经很不错。

2) 为什么说“还没闭环”:少了把“推断 → 因果”钉死的步骤

审稿人可能会问:
“你怎么证明是 缺失 AdeIJ 导致金属/ROS 失衡,而不是其他原因?”

通常闭环至少需要补上一类证据(不一定要做,但逻辑上缺):

A. 互补实验(complementation / rescue)

理想闭环:

  • ΔadeIJ 表型变差
  • 把 adeIJ(或 adeIJK)补回去 → ROS/Cu²⁺/SNP 表型恢复到 WT(rescue)

没有这一步,审稿人可能会担心:

  • 极性效应(polar effect)
  • 二次突变(secondary mutation)
  • 背景差异(background effects)

B. 直接测量“因果中间量”(mechanistic intermediate)

你们推断的是“金属/毒性底物积累 → ROS 上升 → Cu²⁺/SNP 敏感”。
但目前缺少对“中间量”的直接测量,例如:

  • 细胞内 铜含量 是否在 ΔadeIJ 增加(ICP-MS/比色法等)?
  • 是否有更明确的蛋白氧化损伤/Fe–S 破坏指标?
  • 是否存在呼吸链/膜电位异常导致 ROS 增加?

目前是“结果(ROS 高)+ 反应(相关基因上调)”,但还没直接证明“金属积累/底物积累”这一环节。

C. 排除替代解释(alternative explanations)

ΔadeIJ 的高 ROS 也可能来自:

  • 代谢状态改变导致呼吸链泄漏增加
  • 生长状态差异影响 ROS 测定
  • Cu²⁺ 敏感来自包膜改变而非金属外排不足

如果未排除,结论更适合写成 consistent with,而非 crucial determinant

3) “闭环”长什么样(最理想的因果链)

AdeIJ 缺失
细胞内金属/毒性底物积累(直接测到)
ROS 上升(你们已测到)
Cu²⁺/SNP 敏感(你们已测到)
补回 adeIJ 后表型恢复(rescue)

这就是“证据链闭环”。

4) 对写作的建议(不一定要加实验)

投稿时完全可以不补实验,但建议在文字上更稳健:

  • 避免:“AdeIJ is crucial/essential for maintaining …”
  • 推荐:
    • “These data support / are consistent with a role for AdeIJ in …”
    • “We suggest AdeIJ contributes to …”
    • “Further work (e.g., complementation or intracellular metal quantification) would be needed to establish causality.”