RESUMEN
In the present study, molecular methods based on sequencing of clone libraries have been used to provide sequence and the phylogenetic information of ammonia oxidizing bacteria (AOB). Ammonia monooxygenase (amoA) gene, which catalyzed the oxidation of ammonia to hydroxyl amine in the initial rate-determining step of nitrification was targeted for detection and characterization of AOB using gene-specific primers. The amoA genes obtained through the clone library construction are closely affiliated with Nitrosomonas sp. and other uncultured beta proteobacteria. The levels of nucleotide similarity and amino acid similarity ranged from 85-99% and 83-88%, respectively. The level of conservation of the amino acid sequences is 73%. The use of a matrix prepared from abundantly available lignocellulosic agrowaste-bagasse has successfully been demonstrated for biostimulation of AOB in aquaculture environment by supplementing nutritional requirement facilitating the biofilm mode of growth of the autotrophic consortia. Present study is useful in predictability and reliability of the treatment of ammonia in brackishwater aquaculture.
Asunto(s)
Acuicultura/métodos , Agua Dulce/análisis , Nitrosomonadaceae/crecimiento & desarrollo , Nitrosomonadaceae/genética , Oxidorreductasas/genética , Suelo/análisis , Secuencia de Aminoácidos , Secuencia de Bases , Celulosa , Secuencia Conservada/genética , Medios de Cultivo/química , Cartilla de ADN/genética , India , Microscopía Electrónica de Rastreo , Datos de Secuencia Molecular , Nitrosomonadaceae/ultraestructura , Espectroscopía de Fotoelectrones , Salinidad , Análisis de Secuencia de ADN , Homología de Secuencia , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
The intracellular location of the membrane-bound ammonia monooxygenase (AMO) in all genera of ammonia oxidizing bacteria (Nitrosomonas, Nitrosococcus and Nitrosospira) was determined by electron microscopic immunocytochemistry. Polyclonal antibodies recognizing the two subunits, AmoA- and AmoB-proteins, were used for post-embedding labeling. Ultrathin sections revealed that the AmoB-protein was located in all genera on the cytoplasmic membrane. In cells of Nitrosomonas and Nitrosococus additional but less AmoB-labeling was found on the intracytoplasmic membrane (ICM). In contrast to the detection of AmoB-protein, the AmoA-antibodies failed to detect the AmoA-protein. Based on quantitative immunoblots the extent of ICM in Nitrosomonas eutropha was correlated with the amount of AmoA in the cells. The highest extent of ICM and amount of AmoA was found at low ammonium substrate concentrations.
