Geodermatophilus poikilotrophisp. nov.: A Multitolerant Actinomycete Isolated from Dolomitic Marble

Abstract

A novel Gram-reaction-positive, aerobic actinobacterium, tolerant to mitomycin C, heavy metals, metalloids, hydrogen peroxide, desiccation, and ionizing- and UV-radiation, designated G18T, was isolated from dolomitic marble collected from outcrops in Samara (Namibia). The growth range was 15–35°C, at pH 5.5–9.5 and in presence of 1% NaCl, forming greenish-black coloured colonies on GYM Streptomyces agar. Chemotaxonomic and molecular characteristics of the isolate matched those described for other representatives of the genus Geodermatophilus. The peptidoglycan contained meso-diaminopimelic acid as diagnostic diaminoacid. The main phospholipids were phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol, and small amount of diphosphatidylglycerol. MK-9(H4) was the dominant menaquinone and galactose was detected as diagnostic sugar. The major cellular fatty acids were branched-chain saturated acids iso-C16:0 and iso-C15:0 and the unsaturated C17:1 ω8c and C16:1 ω7c. The 16S rRNA gene showed 97.4–99.1% sequence identity with the other representatives of genus Geodermatophilus. Based on phenotypic results and 16S rRNA gene sequence analysis, strain G18T is proposed to represent a novel species, Geodermatophilus poikilotrophi. Type strain is G18T (= DSM 44209T = CCUG 63018T). The INSDC accession number is HF970583. The novel R software package was used to compute the lethal doses with confidence intervals resulting from tolerance experiments.

Geodermatophilus aquaeductus sp. nov., isolated from the ruins of Hadrian’s aqueduct

“…Growth was observed in the presence of 1 % NaCl but not in the presence of 4 and 8 % NaCl. Analysis of cell-wall components revealed the presence of meso-diaminopimelic acid (Cell wall type III), consistent with the descriptions of members of other species of the genus Geodermatophilus (Lechevalier and Lechevalier 1970;Montero-Calasanz et al 2014). The cells were observed to be Gram positive and pleiomorphic, appearing under microscopy as individual cells or associated in cauliflower-like aggregates (Fig.…”

“…The genus currently comprises 17 species mainly isolated from arid and hyperarid environments such as sand and stone, although some were also isolated from rhizospheric soils and lake sediments. Members of the genus Geodermatophilus have been reported to be markedly resistant to adverse environmental conditions such as ultraviolet (UV) light, ionizing radiation (IR), desiccation and heavy metals (Rainey et al 2005;Gtari et al 2012;Montero-Calasanz et al 2013b;Montero-Calasanz et al 2014b). Members of the genus Geodermatophilus have been reported to be markedly resistant to adverse environmental conditions such as ultraviolet (UV) light, ionizing radiation (IR), desiccation and heavy metals (Rainey et al 2005;Gtari et al 2012;Montero-Calasanz et al 2013b;Montero-Calasanz et al 2014b).…”

Blastococcus capsensis sp. nov., isolated from an archaeological Roman pool and emended description of the genus Blastococcus, B. aggregatus, B. saxobsidens, B. jejuensis and B. endophyticus

“…1b-e) and those published by Lee (2006) and Zhu et al (2013), although the absence of phosphatidylglycerol (present in the original descriptions of B. saxobsidens and B. jejuensis) should be noted. Such absence has already been described for other members of the family Geodermatophilaceae (Montero-Calasanz et al, 2014, 2015Hezbri et al 2015aHezbri et al , b, 2016. In addition, it is worth mentioning that the two unidentified phospholipids (PL1 and PL2) observed in BMG 804…”

Stone-dwelling actinobacteria Blastococcus saxobsidens, Modestobacter marinus and Geodermatophilus obscurus proteogenomes

“…These three genera have a complex life cycle and produce remarkably resistant enzymes such as esterases (Essoussi et al, 2010;Jaouani et al, 2012;Normand et al, 2014). They also have the ability to resist adverse environmental conditions such as ultraviolet light, ionizing radiation, desiccation and heavy metals (Rainey et al, 2005;Gtari et al, 2012;Montero-Calasanz et al, 2014, 2015. This resistance to environmental hazards represents a trait of Terrabacteria, a well-supported phylogenetic group composed of Actinobacteria and four other major lineages of eubacteria (Firmicutes, Cyanobacteria, Chloroflexi and Deinococcus-Thermus) that colonized land 3.05-2.78 Ga (Tunnacliffe and Lapinski, 2003;Battistuzzi et al, 2004;Battistuzzi and Hedges, 2009).…”