Actinopolyspora biskrensis sp. nov., a Novel Halophilic Actinomycete Isolated from Northern Sahara

Genome-based reclassification of Actinopolyspora righensis Meklat et al. 2013 as a later heterotypic synonym of Actinopolyspora lacussalsi Guan et al. 2013 and description of Actinopolyspora lacussalsi subsp. lacussalsi subsp. nov. and Actinopolyspora lacussalsi subsp. righensis subsp. nov

A genome led phylophasic study was designed to determine the taxonomic status of a strain, DSM 45956, recovered from a Saharan desert soil. A wealth of taxonomic data, including average nucleotide identity and DNA:DNA hybridization (DDH) values, showed that the isolate and the type strains of Actinopolyspora lacussalsi and Actinopolyspora righensis belong to the same species. Consequently, it is proposed that A. righensis is a heterotypic synonym of A. lacussalsi. Similarly, DDH values and associated phenotypic data show that A. lacussalsi contains two subspecies, A. lacussalsi subsp. lacussalsi and A. lacussalsi subsp. righensis which includes isolate DSM 45956.

Actinobacteria Derived from Algerian Ecosystems as a Prominent Source of Antimicrobial Molecules

Actinobacteria, in particular "rare actinobacteria" isolated from extreme ecosystems, remain the most inexhaustible source of novel antimicrobials, offering a chance to discover new bioactive metabolites. This is the first overview on actinobacteria isolated in Algeria since 2002 to date with the aim to present their potential in producing bioactive secondary metabolites. Twenty-nine new species and one novel genus have been isolated, mainly from the Saharan soil and palm groves, where 37.93% of the most abundant genera belong to Saccharothrix and Actinopolyspora. Several of these strains were found to produce antibiotics and antifungal metabolites, including 17 new molecules among the 50 structures reported, and some of these antibacterial metabolites have shown interesting antitumor activities. A series of approaches used to enhance the production of bioactive compounds is also presented as the manipulation of culture media by both classical methods and modeling designs through statistical strategies and the associations with diverse organisms and strains. Focusing on the Algerian natural sources of antimicrobial metabolites, this work is a representative example of the potential of a closely combined study on biology and chemistry of natural products.

Actinopolyspora salinaria sp. nov., a halophilic actinomycete isolated from solar saltern soil

The taxonomic position of the halophilic actinobacterial strain, HS05-03T, isolated from solar saltern soil, was determined using a polyphasic approach. Phylogenetic analysis based on the 16S rRNA gene sequence of the strain showed that it formed a distinct evolutionary lineage in the genus Actinopolyspora. The organism was most closely related to the type strains of the species Actinopolyspora xinjiangensis (98.0% similarity), Actinopolyspora righensis (97.9% similarity), Actinopolyspora lacussalsi (97.9% similarity) and Actinopolyspora erythraea (97.8% similarity). The whole-organism hydrolysates contained meso-diaminopimelic acid, arabinose, galactose and ribose. The predominant menaquinones were found to be MK-9(H4) and MK-10(H4). The acyl type of the peptidoglycan was N-acetyl. The diagnostic phospholipid detected was phosphatidylcholine. The predominant cellular fatty acids were iso-C16 : 0, anteiso-C17:0 and iso-C15:0. The G+C content of the genomic DNA was 69.9 mol%. DNA-DNA hybridization values between strain HS05-03T and the type strains of the most closely related species were below the 70 % threshold. On the basis of the phenotypic and genotypic data, it is proposed that strain HS05-03T represents a novel species of the genus Actinopolyspora, with the name Actinopolyspora salinaria sp. nov. The type strain is HS05-03T (=BCC 51286T=NBRC 109078T).

Bounagaea algeriensis gen. nov., sp. nov., an extremely halophilic actinobacterium isolated from a Saharan soil of Algeria

A novel halophilic actinobacterium strain, designated H8(T), was isolated from a Saharan soil sample collected in El-Goléa, South Algeria. Strain H8(T) was identified as representing a new genus using a polyphasic taxonomic approach. Phylogenetic analysis revealed that strain H8(T) shared the highest degree of 16S rRNA gene sequence similarity with 'Mzabimyces algeriensis' DSM 46680(T) (93.0 %), Saccharopolyspora ghardaiensis DSM 45606(T) (91.2 %), Halopolyspora alba DSM 45976(T) (90.8 %) and Actinopolyspora mortivallis DSM 44261(T) (90.0 %). The strain was found to grow optimally at 28-35 °C, at pH 6.0-7.0, and in the presence of 15-25 % (w/v) NaCl. The substrate mycelium was observed to be well developed and fragmented in liquid medium and on solid medium. The aerial mycelium was observed to be moderately abundant and to form long chains with non-motile, smooth-surfaced and ovoid or spherical spores at maturity. The cell wall of strain H8(T) was found to contain meso-diaminopimelic acid. The whole-cell hydrolysates were found to mainly contain arabinose and galactose. The diagnostic phospholipid detected was phosphatidylcholine, and MK-9(H4), MK-9(H2) and MK-10(H2) were found to be the predominant menaquinones. The major cellular fatty acids were determined to be anteiso-C17:0 and iso-C15:0. The genomic DNA G+C content of strain H8(T) was determined to be 71.3 mol%. The genotypic and phenotypic data showed that the strain represents a novel genus and species, for which the name Bounagaea algeriensis gen. nov., sp. nov. is proposed, with the type strain H8(T) (=DSM 45966(T) = CECT 8470(T)).

List of new names and new combinations previously effectively, but not validly, published

The purpose of this announcement is to effect the valid publication of the following effectively published new names and new combinations under the procedure described in the Bacteriological Code (1990 Revision). Authors and other individuals wishing to have new names and/or combinations included in future lists should send three copies of the pertinent reprint or photocopies thereof, or an electronic copy of the published paper to the IJSEM Editorial Office for confirmation that all of the other requirements for valid publication have been met. It is also a requirement of IJSEM and the ICSP that authors of new species, new subspecies and new combinations provide evidence that types are deposited in two recognized culture collections in two different countries. It should be noted that the date of valid publication of these new names and combinations is the date of publication of this list, not the date of the original publication of the names and combinations. The authors of the new names and combinations are as given below. Inclusion of a name on these lists validates the publication of the name and thereby makes it available in the nomenclature of prokaryotes. The inclusion of a name on this list is not to be construed as taxonomic acceptance of the taxon to which the name is applied. Indeed, some of these names may, in time, be shown to be synonyms, or the organisms may be transferred to another genus, thus necessitating the creation of a new combination.