title: Characterization of the plant growth promoting bacterium, Enterobacter cloacae MSR1, isolated from roots of non-nodulating Medicago sativa.
abstract: The aim of the present study was to characterize the endophytic bacterial strain designated MSR1 that was isolated from inside the non-nodulating roots of Medicago sativa after surface-sterilization. MSR1 was identified as Enterobacter cloacae using both 16S rDNA gene sequence analysis and API20E biochemical identification system (Biomerieux, France). Furthermore, this bacterium was characterized using API50CH kit (Biomerieux, France) and tested for antibacterial activities against some food borne pathogens. The results showed that E. cloacae consumed certain carbohydrates such as glycerol, d-xylose, d-maltose and esculin melibiose as a sole carbon source and certain amino acids such as arginine, tryptophan ornithine as nitrogen source. Furthermore, MSR1 possessed multiple plant-growth promoting characteristics; phosphate solubility, production of phytohormones acetoin and bioactive compounds. Inoculation of Pisum sativum with MSR1 significantly improved the growth parameters (the length and dry weight) of this economically important grain legume compared to the non-treated plants. To our knowledge, this is the first report addressing E. cloacae which exist in roots of alfalfa growing in Al-Ahsaa region. The results confirmed that E. cloacae exhibited traits for plant growth promoting and could be developed as an eco-friendly biofertilizer for P. sativum and probably for other important plant species in future.
authors: Biological Sciences Department, College of Science, King Faisal University, Saudi Arabia; Botany and Microbiology Department, Faculty of Science, University of Beni-Suef, Beni-Suef, Egypt.
authors: Ashraf Y Z
authors: AY
authors: Khalifa
authors: Biological Sciences Department, College of Science, King Faisal University, Saudi Arabia.
authors: Abdel-Moneium
authors: AM
authors: Alsyeeh
authors: Biological Sciences Department, College of Science, King Faisal University, Saudi Arabia.
authors: Mohammed A
authors: MA
authors: Almalki
authors: Department of Food Science and Nutrition, College of Agricultural and Food Sciences, King Faisal University, Saudi Arabia; Department of Special Food and Nutrition, Food Technology Research Institute, Agricultural Research Center, Giza, Egypt.
authors: Farag A
authors: FA
authors: Saleh
keywords: Bacterial endophytes; Enterobacter cloacae; Pisum sativum