Cultivable Nitrogen Fixing Bacteria from Extremely Alkaline-Saline Soils  

作　　者：Yendi E. Navarro-Noya Marco Luna-Guido Luc Dendooven Yendi E. Navarro-Noya;Marco Luna-Guido;Luc Dendooven(CONACYT-Tlaxcala Autonomous University, Tlaxcala, Mexico;Laboratory of Soil Ecology, ABACUS-Cinvestav, Mexico City, Mexico)

机构地区：[1]CONACYT-Tlaxcala Autonomous University, Tlaxcala, Mexico [2]Laboratory of Soil Ecology, ABACUS-Cinvestav, Mexico City, Mexico

出　　处：《Advances in Microbiology》2016年第6期412-423,共12页微生物学（英文）

摘　　要：Three soils with different Electrolytic Conductivity (EC) from the former Lake Texcoco (soil with low EC 1.2 dS·m^-1, medium with EC 83.1 - 107.8 dS·m^-1, and high with EC 137.3 - 152.5 dS•m^-1) were used to isolate nitrogen-fixing bacterial strains through enrichment cultures in nitrogen-free media. The medium and high EC in the soil affected negatively the nitrogen-fixing activity, which was generally ten times lower compared to the activity in the soil with low EC. Twenty-one bacterial strains were isolated, identified and characterized for their nitrogen fixation capacity. The diazotrophic genetic potential of all isolates was confirmed by amplification and sequencing of partial nifH and nifD genes and diazotrophic activity quantified by the acetylene reduction assay. Azospirillum brasilense, and several species of Paenibacillus (P. fujiensis, P. durus, P. borealis, P. graminis, P. massiliensis and P. wynnii) were identified. Isolates belonging to the Paenibacillus genus were found in the three soils. Paenibacillus fujiensis and P. durus showed a high nitrogenase activity. The phylograms based on nifH and nifD gene sequences were consistent with 16S rRNA gene phylogeny.Three soils with different Electrolytic Conductivity (EC) from the former Lake Texcoco (soil with low EC 1.2 dS·m^-1, medium with EC 83.1 - 107.8 dS·m^-1, and high with EC 137.3 - 152.5 dS•m^-1) were used to isolate nitrogen-fixing bacterial strains through enrichment cultures in nitrogen-free media. The medium and high EC in the soil affected negatively the nitrogen-fixing activity, which was generally ten times lower compared to the activity in the soil with low EC. Twenty-one bacterial strains were isolated, identified and characterized for their nitrogen fixation capacity. The diazotrophic genetic potential of all isolates was confirmed by amplification and sequencing of partial nifH and nifD genes and diazotrophic activity quantified by the acetylene reduction assay. Azospirillum brasilense, and several species of Paenibacillus (P. fujiensis, P. durus, P. borealis, P. graminis, P. massiliensis and P. wynnii) were identified. Isolates belonging to the Paenibacillus genus were found in the three soils. Paenibacillus fujiensis and P. durus showed a high nitrogenase activity. The phylograms based on nifH and nifD gene sequences were consistent with 16S rRNA gene phylogeny.

关 键 词：DIAZOTROPHS Extremophyles Haloalkaline HALOTOLERANT PAENIBACILLUS 

分 类 号：Q78[生物学—分子生物学]