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Two Streptomyces strains, labeled as MZ03-37T and MZ03-48, were isolated from two different samples, a mucolite-type speleothem and a microbial mat on the walls of a lava tube from La Palma Island (Canary Islands). Phylogenetic analysis based on concatenated sequences of six housekeeping genes indicated that both strains belonged to the same species. The closest relatives for both strains were Streptomyces palmae CMU-AB204T (98.71%), Streptomyces catenulae NRRL B-2342T (98.35%), and Streptomyces ramulosus NRRL B-2714T (98.35%). Multi-locus sequence analysis (MLSA), based on five house-keeping gene alleles (i.e., atpD, gyrB, recA, rpoB , and trpB), indicated that both isolated strains were closely related to S. catenulae NRRL B-2342T. Whole-genome average nucleotide identity (ANI) scores of both strains were in the threshold value for species delineation with the closest species. Both strains presented a G+C content of 72.1 mol%. MZ03-37T was light brown in substrate and white in aerial mycelium, whereas MZ03-48 developed a black aerial and substrate mycelium. No pigment diffusion was observed in both strains. They grew at 10°C−37°C (optimum 28°C−32°C) and in the presence of up to 15% (w/v) NaCl. MZ03-37T grew at pH 5–10 (optimal 6–9), whereas MZ03-48 grew at pH 4–11 (optimal 5–10). LL-Diaminopimelic acid was the main diamino acid identified. The predominant fatty acids in both strains were iso-C16:0, anteiso-C15:0, C16:0, and iso-C14:0. The major isoprenoid quinones were MK-9(H6) and MK-9(H8), and the main polar lipids were aminolipid, phospholipid, and phosphoglycolipid. In silico analyses for functional annotation predicted the presence of gene clusters involved in resistome mechanisms and in the synthesis of described antimicrobials such as linocin-M18 and curamycin, as well as different genes likely involved in mechanisms for active compound synthesis, both already described and not discovered so far. On the basis of their phylogenetic relatedness and their phenotypic and genotypic features, the strains MZ03-37T and MZ03-48 represented a novel species within the genus Streptomyces , for which the name Streptomyces benahoarensis sp. nov. is proposed. The type strain is MZ03-37T (= CECT 9805 = DSMZ 8002); and MZ03-48 (= CECT 9806 = DSMZ 8011) is a reference strain. [ABSTRACT FROM AUTHOR]

Two Gram-positive, catalase-positive, oxidase-negative, motile, endospore-forming, rod-shaped bacteria, designated as 0911MAR22V3T and 0911TES10J4, were isolated from air samples collected in two show caves, located in Andalusia, Southern Spain. Phylogenetic analysis based on 16S rRNA gene sequences indicated that both strains were indistinguishable and they were most closely related to Bacillus humi DSM 16318T (98%). DNA–DNA hybridization values of the strain 0911MAR22V3T with respect to strain 0911TES10J4 and B. humi DSM 16318T were 76.8% (73.9%, reciprocal) and 56.9% (63.3%, reciprocal analysis), respectively. Whole genome average nucleotide identity (ANI) values of both strains were in the threshold value for species delineation and less than 85% with B. humi . Strains 0911MAR22V3T and 0911TES10J4 grew at 10–47 °C (optimum 37 °C), at pH 6–9.5 and with 0–8% (w/v) NaCl (optimum 1%). In both strains the dominant isoprenoid quinone was MK-7, the major cellular polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, and two more phospholipids, the predominant fatty acids were iso-C15:0 and anteiso-C15:0 and the DNA G + C content was 38 mol%. On the basis of their phylogenetic relatedness and their phenotypic and genotypic features, the strains 0911MAR22V3T and 0911TES10J4 should be attributed to a novel species within the genus Bacillus, for which the name Bacillus onubensis sp. nov. is proposed. The type strain is 0911MAR22V3T (=LMG 27963T = CECT 8479T); and strain 0911TES10J4 (CECT 8478) is a reference strain. [ABSTRACT FROM AUTHOR]