MORPHOLOGICAL, PHYSIOLOGICAL, AND MOLECULAR CHARACTERIZATION OF ACTINOMYCETES ISOLATED FROM DRY SOIL, ROCKS, AND MONUMENT SURFACES

In an extended study on the biodiversity of rock-dwelling bacteria, th e colony and cell morphology, physiology, protein patterns, and 16S rD NA sequences of 17 bacterial strains isolated from different surfaces of rocks, stones, and monuments and from various geographical location s were characterized. All except one strain, which was found to be a B acillus, were members of the order Actinomycetales. The majority of ti e strains either were closely related to Geodermatophilus obscurus, wh ich was also analyzed in this study, or Formed a closely related siste r taxon. All of these strains were isolated from the surface of marble in Namibia and Greece and from limestone from the Negev desert. Israe l. One strain, G10, of Namibia origin was equidistantly related to Geo dermatophilus obscurus, Frankia alni, Sporichthya polymorpha, and Acid othermus cellulolyticus. Three strains from rock varnish in the Mojave desert, California, were found to be highly related to Arthrobacter ( formerly Micrococcus) agilis. All clusters could be confined from resu lts of studies on morphological and physiological properties and from banding patter ns of whole cell proteins. Based on the results of test s, four additional strains were assigned to the lineage defined by str ain G10.