Autotrophic microorganisms catalyze the entry of dissolved inorganic carbon (DIC; = CO₂ + HCO₃⁻ + CO₃²⁻) into the biological component of the global carbon cycle, despite dramatic differences in DIC abundance and composition in their sometimes extreme environments. ‘Cyanobacteria’ are known to have CO₂ concentrating mechanisms (CCMs) to facilitate growth under low CO₂ conditions. These CCMs consist of carboxysomes, containing enzymes ribulose 1,5-bisphosphate oxygenase and carbonic anhydrase, partnered to DIC transporters. CCMs and their DIC transporters have been studied in a handful of other prokaryotes, but it was not known how common CCMs were beyond ‘Cyanobacteria’. Since it had previously been noted that genes encoding potential transporters were found neighboring carboxysome loci, α-carboxysome loci were gathered from bacterial genomes, and potential transporter genes neighboring these loci are described here. Members of transporter families whose members all transport DIC (CHC, MDT, and Sbt) were common in these neighborhoods, as were members of the SulP transporter family, many of which transport DIC. 109 of 115 taxa with carboxysome loci have some form of DIC transporter encoded in their genomes, suggesting that CCMs consisting of carboxysomes and DIC transporters are widespread not only among ‘Cyanobacteria’, but also among members of ‘Proteobacteria’ and ‘Actinobacteria’.

中文翻译：

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编码多种溶解性无机碳转运蛋白的基因的多样性和普遍性提示了细菌多个门的CO2浓缩机制的普遍性和功能均一性。

自养微生物催化溶解的无机碳的条目（DIC; = CO ₂  + HCO ₃ ^- + CO ₃ ^2-）到全球碳循环的生物成分，尽管在DIC丰度和组合物在其有时极端环境的巨大差异。已知“蓝细菌”具有CO ₂浓缩机制（CCM），以促进在低CO ₂条件下的生长。这些CCM由包含与DIC转运蛋白结合的核糖1,5-双磷酸加氧酶和碳酸酐酶的羧基体组成。CCM及其DIC转运蛋白已经在少数其他原核生物中进行了研究，但尚不了解普通CCM的范围'蓝细菌'。由于先前已经指出，发现了编码潜在转运蛋白的基因邻近羧基体位点，因此从细菌基因组中收集了α-羧化酶基因座，此处描述了邻近这些基因座的潜在转运蛋白基因。在这些社区中，所有成员都运送DIC（CHC，MDT和Sbt）的运输者家庭成员以及这些运输DIC的SulP运送者家庭成员都很常见。115个带有羧基体位点的分类单元中的109个在其基因组中编码了某种形式的DIC转运蛋白，这表明由羧基体和DIC转运蛋白组成的CCM不仅在“蓝藻”中广泛存在，而且在“变形杆菌”和“放线杆菌”中也很普遍。