ISOLATION AND CHARACTERIZATION OF NOVEL ALKALIPHILES FROM BAUXITE-PROCESSING WASTE AND DESCRIPTION OF BACILLUS-VEDDERI SP-NOV, A NEW OBLIGATE ALKALIPHILE

Three novel alkaliphilic bacteria were isolated and characterized following enrichment at pH 10, using mud from a bauxite-processing red mud tailing pond as source material. The isolates, designated strains JaA, JaD and JaH were aerobic, Gram-positive, spore-forming, mesophilic rods which were motile by means of peritrichously arranged flagella. Strains JaD and JaH could also grow anaerobically. All three isolates had pH optima for growth of approximately 10, with strains JaD and JaH obligate alkaliphiles. Strains JaA and JaD grew in the presence of 10% (w/v) NaCl while strain JaH could grow in the presence of up to 7.5% (w/v) NaCl. The mole% G+C content of purified DNA was 41.3% for strain JaA, 41.8% for strain JaD and 38.3% for strain JaH. The new isolates appear to be members of the genus Bacillus but 16s rDNA sequence analysis and sodium dodecyl sulfate-polyacrylamide gel electrophoresis comparisons of whole cell protein profiles, as well as nutritional, biochemical and morphological traits indicated the new isolates are not members of any validly published Bacillus species. The epithet Bacillus vedderi is proposed for strain JaH.