Abstract Ammonia-oxidizing bacteria (AOB) and aerobic methane oxidizing-bacteria (MOB) were studied in three extreme soils of the former Lake Texcoco, Mexico, with pH ranging from 8.5 to 10.5 and electrolytic conductivity (EC) from 0.67 to 84.76 dS m−1, and in two arable soils. Soil DNA was extracted with three different methods and total DNA was used as a template to amplify the pmoA and amoA functional genes and subsequently sequenced by pyrosequencing. The amoA gene sequences clustered as uncultured AOB dominated in the Texcoco soils, while Nitrosospira was dominant in the arable soils. Sequences of MOB associated with Nitrosococcus-rel (Type I) dominated (>85%) in the Texcoco soils, but they were more diverse in the arable soils, for example, JR2, JR3, Methylocaldum USC-g (Type I), USC-a (Type II) and gp23 (pxmA). Aerobic methane oxidizing-bacteria and AOB microbial diversity were significantly related to EC and pH (p < 0.05). As such, the lower MOB and AOB microbial diversity in the Texcoco soil compared to the arable soil was determined by its higher EC and pH.

中文翻译：

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前特斯科科湖极盐碱土壤中 amoA 和 pmoA 基因的多样性

摘要 在墨西哥特斯科科湖的三个极端土壤中研究了氨氧化细菌（AOB）和好氧甲烷氧化细菌（MOB），pH 范围为 8.5 至 10.5，电导率（EC）为 0.67 至 84.76 dS m −1，并且在两个耕地土壤中。用三种不同的方法提取土壤 DNA，以总 DNA 为模板扩增 pmoA 和 amoA 功能基因，随后通过焦磷酸测序进行测序。amoA 基因序列聚集为未培养的 AOB 在 Texcoco 土壤中占主导地位，而 Nitrosospira 在可耕土壤中占主导地位。与 Nitrosococcus-rel（I 型）相关的 MOB 序列在 Texcoco 土壤中占主导地位（>85%），但它们在可耕土壤中更加多样化，例如，JR2、JR3、Methylocaldum USC-g（I 型）、USC -a（II 型）和 gp23（pxmA）。需氧甲烷氧化细菌和AOB 微生物多样性与EC 和pH 显着相关（p < 0.05）。因此，与可耕土壤相比，Texcoco 土壤中较低的 MOB 和 AOB 微生物多样性是由其较高的 EC 和 pH 值决定的。