Di Meglio Leonardo, Santos Fernando, Gomariz María, Almansa Cristina, López Cristina, Antón Josefa, Nercessian Débora
Instituto de Investigaciones Biológicas, Facultad de Ciencias Exactas y Naturales, UNMDP - CONICET, Funes 3250 4° nivel, 7600 Mar del Plata, Argentina.
Departamento de Fisiología, Genética y Microbiología, Facultad de Ciencias, Universidad de Alicante, 03690 San Vicente del Raspeig, España.
FEMS Microbiol Ecol. 2016 Dec;92(12). doi: 10.1093/femsec/fiw184. Epub 2016 Sep 7.
Seasonal sampling was carried out at three Argentinian salterns, Salitral Negro (SN), Colorada Grande (CG) and Guatraché (G), to analyze abiotic parameters and microbial diversity and dynamics. Microbial assemblages were correlated to environmental factors by statistical analyses. Principal component analysis of the environmental data grouped SN and CG samples separately from G samples owing to G's higher pH values and sulfate concentration. Differences in microbial assemblages were also found. Many archaeal sequences belonged to uncultured members of Haloquadratum and Haloquadratum-related genera, with different environmental optima. Notably, nearly half of the archaeal sequences were affiliated to the recently described 'Candidatus Haloredividus' (phylum Nanohaloarchaeota), not previously detected in salt-saturated environments. Most bacterial sequences belonged to Salinibacter representatives, while sequences affiliated to the recently described genus Spiribacter were also found. Seasonal analysis showed at least 40% of the microbiota from the three salterns was prevalent through the year, indicating they are well adapted to environmental fluctuations. On the other hand, a minority of archaeal and bacterial sequences were found to be seasonally distributed. Five viral morphotypes and also eukaryal predators were detected, suggesting different mechanisms for controlling prokaryotic numbers. Notably, Guatraché was the saltern that harbored the highest virus-to-cell ratios reported to date for hypersaline environments.
在阿根廷的三个盐场，即黑盐沼（SN）、大科罗拉多盐沼（CG）和瓜特拉切盐沼（G）进行了季节性采样，以分析非生物参数以及微生物多样性和动态变化。通过统计分析将微生物群落与环境因素进行关联。环境数据的主成分分析将SN和CG的样本与G的样本分开归类，这是因为G的pH值和硫酸盐浓度较高。同时也发现了微生物群落的差异。许多古菌序列属于未培养的盐方形嗜盐菌属及与盐方形嗜盐菌相关的属，它们具有不同的环境最适条件。值得注意的是，近一半的古菌序列隶属于最近描述的“候选盐还原菌”（纳诺嗜盐古菌门），此前在盐饱和环境中未检测到该菌。大多数细菌序列属于盐杆菌属代表，同时也发现了隶属于最近描述的螺旋杆菌属的序列。季节性分析表明，这三个盐场中至少40%的微生物群在全年都很普遍，这表明它们能很好地适应环境波动。另一方面，发现少数古菌和细菌序列存在季节性分布。检测到了五种病毒形态类型以及真核捕食者，这表明存在控制原核生物数量的不同机制。值得注意的是，瓜特拉切盐沼是迄今为止报道的超盐环境中病毒与细胞比率最高的盐场。
