TL;DR: An investigation into the occurrence and biodiversity of Geodermatophilaceae on 78 samples of altered stone surfaces from 24 monuments and natural stones in the Mediterranean basin found that the total microbial counts ranged between 0 and 10 cfu g(-1) dry weight, suggesting that there is a wide genetic diversity at the microsite level.
Abstract: An investigation was made into the occurrence and biodiversity of Geodermatophilaceae on 78 samples of altered stone surfaces from 24 monuments and natural stones in the Mediterranean basin; it was found that the total microbial counts ranged between 0 and 10(7) cfu g(-1) dry weight. Members of the Geodermatophilaceae family were isolated from 22 of the 78 samples examined, with the incidence of Geodermatophilaceae colonies in the cultivable population ranging from 1% to 100%. The highest percentage was found in six samples of markedly deteriorated stone. Sixty-five strains randomly isolated from the plates were clustered in six different groups by amplified 16S rDNA restriction analysis (ARDRA) using five different restriction enzymes. Twenty-five strains, representing all the ARDRA haplotypes, were characterized further by partial sequencing (350-550 bp) of the 16S rDNA and by analysing 76 morphological, metabolic and physiological properties. The strains were associated with three well-separated clusters of the genera Geodermatophilus, Blastococcus and Modestobacter. On the basis of 16S rDNA sequence and ARDRA analysis, only two strains were found to be related to the two reference strains of Geodermatophilus. All the others could be grouped with Blastococcus aggregatus (19 strains) or the Antarctic species Modestobacter multiseptatus (44 strains), suggesting that it is these two groups, rather than Geodermatophilus, that tend to colonize the stone surfaces, and that Modestobacter-like strains are also found in temperate/Mediterranean climates. From the BOX-polymerase chain reaction (PCR) data, it can be seen that the Modestobacter-like strains, belonging to the most represented ARDRA haplotype (haplotype B, 34 strains), are very polymorphic and that, over a stone surface, there is a wide genetic diversity at the microsite level.
TL;DR: The stress resistance profiles of M. multiseptatus and B. saxobsidens were reflected in different calcarenite colonization patterns, suggesting that the response to light- and desiccation-induced oxidative stress is an important driver for niche colonization in the stone biotope.
TL;DR: Oligotrophic PYGV medium, inoculated with soils from Linnaeus Terrace (1600 m, Antarctica), yielded four aerobic actinomycetes with short rods, multiple and irregular septa and often motile buds that represent a new genus, Modestobacter gen. nov.
Abstract: Oligotrophic PYGV medium, inoculated with soils from Linnaeus Terrace (1600 m, Antarctica), yielded four aerobic actinomycetes with short rods, multiple and irregular septa and often motile buds. Cells were 1.0-2.8 x 1.0-3.0 microm and colonies were beige to pink. The isolates were nearly identical in physiological and biochemical tests. Three strains grew from 0 degrees C to 25-28 degrees C, but one was psychrophilic with a maximum growth temperature of 20 degrees C. Carbon sources utilized were D-glucose, D-galactose, lactose, sucrose or mannitol; malate, succinate, fumarate, pyruvate or glutarate were decarboxylated aerobically. Peptone and yeast extract were the preferred nitrogen sources. Nitrate was reduced aerobically or anaerobically. Cell walls contained meso-diaminopimelic acid, glutamate, alanine, glycine, galactose, glucose and ribose. Major fatty acids of strains AA-802, -824, -825 and -826T were n18:1, i16:0 and ai17:0. Major respiratory quinones were MK-9(H4) and MK-8(H4). Polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol. Phosphatidylglycerol was found in most strains. The DNA G+C contents were 68-70 mol%. In 16S rDNA analyses, similarity values obtained for 500 nucleotides from the 5' terminus were > 99.5%. Almost complete sequences from AA-826T and -825 were 99.9% similar. Strain AA-826T belonged to a novel cluster of desert soil and rock isolates within the Geodermatophilaceae and was equidistantly related to members of Geodermatophilus and to a Blastococcus lineage. The four isolates represent a new genus, Modestobacter gen. nov., with Modestobacter multiseptatus sp. nov. as the type species. The type strain, Modestobacter multiseptatus AA-826T, was deposited in the DSMZ as DSM 44406T.
TL;DR: The family 'Geodermatophilaceae' is described, which includes the recently described genus Modestobacter, and the type genus of the family is Geodmatophilus.
Abstract: The family name ‘Geodermatophilaceae’ was first published by Normand et al. (1996) to contain the genera Geodermatophilus and Blastococcus, but a formal description and the designation of the type genus were not included, thus making the name invalid. Since then, the genus Modestobacter has been described as a member of the family ‘Geodermatophilaceae’ by Mevs et al. (2000) . We hereby formally describe the family ‘Geodermatophilaceae’ which includes the recently described genus Modestobacter. The type genus of the family is Geodermatophilus.
TL;DR: Ten Gram-positive, aerobic bacterial strains with coccoid cells occurring singly, in pairs, tetrads and small aggregates were isolated from the surface of marble and calcareous stones, revealing a strain-rich cluster containing BC444T, which will be described as a novel species of Blastococcus sp.
Abstract: Ten Gram-positive, aerobic bacterial strains with coccoid cells occurring singly, in pairs, tetrads and small aggregates were isolated from the surface of marble and calcareous stones. The peptidoglycan contained meso-diaminopimelic acid as the diagnostic diamino acid. The major menaquinone was MK-9(H4). The cellular fatty acid pattern consisted mainly of iso-branched chain components. According to their phylogenetic position, the organisms are members of the family Geodermatophilaceae, clustering close to Blastococcus aggregatus DSM 4725T. Based on a combination of phenotypic, chemotaxonomic and genotypic characteristics, strain BC444T and seven relatives group apart from strains BC412 (=DSM 44517) and BC521 (=DSM 44518), which themselves form two individual lineages. DNA-DNA reassociation studies revealed that members of the three lineages were only remotely related to B. aggregatus DSM 4725T; as the strain-rich cluster containing BC444T shared low DNA similarity values with strains BC412 and BC521, it will be described as a novel species of Blastococcus, for which the name Blastococcus saxobsidens sp. nov. is proposed. The type strain is BC444T (=DSM 44509T=NRRL 24246T).