• Molecular Identification and Isolation of Novel Uricase-Positive Bacteria from Soil Enriched with Poultry Manure
  • Parisa Pakbaz,1 Nematollah Razmi,2 Nima Bahador,3 Safoura Sameni,4,*
    1. Department of Biochemistry, Shiraz Branch, Islamic Azad University, Shiraz, Iran
    2. Department of Biochemistry, Shiraz Branch, Islamic Azad University, Shiraz, Iran
    3. Department of Microbiology, Shiraz Branch, Islamic Azad University, Shiraz, Iran
    4. Department of Biochemistry, Shiraz Branch, Islamic Azad University, Shiraz, Iran


  • Introduction: Soils, especially agricultural soils contain a collection of minerals, organic matter, and beneficial microorganisms. Soil microorganisms, including bacteria, are capable of biosynthesis and secretion of many enzymes, which can decompose biomolecules of the surrounding sewage and fertilizers. Microbial activity will improve the volatilization of ammonia from poultry manure, denoting that uric acid, as the dominant non-protein nitrogenous compound form of this fertilizer, will be converted into allantoin by microbial uricase. This research aims to identify and isolate the uricase-producing bacteria from soil samples enriched with poultry manure from Shiraz, Iran.
  • Methods: In this study, 20 soil samples enriched with poultry manure from different parts of South East Shiraz, were diluted and the supernatants were analyzed for bacterial isolation. Later the bacteria were cultured in either minimal uric acid or uric acid-free medium. Uricase-positive bacteria, fed on uric acid as source of carbon and nitrogen. Different microbial and biochemical tests including gram stain, catalase, oxidase, nitrate reduction, sulfide, indole motility, hydrolysis of starch, and gelatin hydrolysis were performed. Lastly, uricase-producing bacterial strains were isolated through a PCR test.
  • Results: Twenty randomly selected soil samples were screened for microbial activity. Out of 9 bacterial species, 2 novel uricase-positive bacteria were isolated. Following the molecular examination, as confirmed by NCBI blast analysis, one strain was identified as Sphingobium sp. C1-1 and the other one was Bacillus flexus strain Til_Wak_24.
  • Conclusion: The results of this study validate the potential of poultry manure enriched soils in producing microbial uricase enzyme.
  • Keywords: Uricase positive bacteria, Minimal media, Uric Acid, Soil, Poultry Manure