Typification of urban habitats,with ant assemblages of Moscow city taken as an example

A typification of Moscow city habitats is undertaken, based on their consideration as mosaic of patches and using such fundamental parameters as habitat origin (soil type), floristic composition, vegetation structure, and area of the biotopes. Altogether, 11 habitat types are distinguished: lawns, agrocenoses, xerophytic and mesophytic meadows, tall weeds, boulevards, small degenerative parks, small oppressed artificial parks, landscape parks, forest parks, and technocenoses. Such a classification is primarily useful for studying ants. The present paper describes the basic structure of ant assemblages in most types of urban biocenoses. The main pool of Moscow’s ant species ranked by their occurrence is as follows: Lasius niger (87%), Myrmica rugulosa (44%), Myrmica rubra (33%), Formica cunicularia (11%), Myrmica ruginodis (10%), etc. Leaf litter removal with a rake was shown to negatively affect the numbers, biomass, and species diversity of ant communities in urban areas with trees. The most stable two-species ant community revealed in Moscow City, termed an “elementary urban community,” consists of L. niger and M. rugulosa, with the former always outnumbering the latter.     

Antagonistic activity of soil acidophilic actinomycetes

It has been shown that soil acidophilic actinomycetes (mycelial prokaryotes with a growth optinum between pH 3 and 7) markedly differ from neutrophilic actinomycetes in antimicrobial activity: the former are more active against fungi and yeasts, whereas the latter effectively suppress Gram-positive bacteria. Acidophilic streptomycetes actively inhibit the growth of phytopathogenic fungi, especially on acidic media.     

Peculiarities of Growth and Morphological Differentiation of Acidophilic and Neutrophilic Soil Streptomycetes

Acidophilic actinomycetes are shown to possess a special mechanism of adaptation to low pH conditions, which shows up in their ability to grow faster on acidified than on neutral media and to adjust the pH of the medium to a level favorable for the formation of aerial mycelium and spores. On nutrient media with pH below 5, neutrophilic actinomycetes either fail to grow or grow much slower than on neutral media; they do not alkalize the medium and do not form aerial mycelium.     

Amycolatopsis camponoti sp. nov., new tetracenomycin-producing actinomycete isolated from carpenter ant Camponotus vagus

An actinobacterial strain A23^T, isolated from adult ant Camponotus vagus collected in Ryazan region (Russia) and established as tetracenomycin X producer, was subjected to a polyphasic taxonomic study. Morphological characteristics of this strain included well-branched substrate mycelium and aerial hyphae fragmented into rod-shaped elements. Phylogenetic analyses based on 16S rRNA gene and genome sequences showed that strain A23^T was most closely related to Amycolatopsis pretoriensis DSM 44654^T. Average nucleotide identity and digital DNA–DNA hybridization values between the genome sequences of isolate A23^T and its closest relative, Amycolatopsis pretoriensis DSM 44654^T, were 39.5% and 88.6%, which were below the 70% and 95–96% cut-off point recommended for bacterial species demarcation, respectively. The genome size of the isolate A23^T was 10,560,374 bp with a DNA G?+?C content of 71.2%. The whole-cell hydrolysate contained meso-diaminopimelic acid and arabinose and galactose as main diagnostic sugars as well as ribose and rhamnose. It contained MK-9(H4) as the predominant menaquinone and iso-C_16:0, iso-C_15:0, anteiso-C_17:0 and C_16:0 as the major cellular fatty acids. Diphosphatidylglycerol and phosphatidylethanolamine prevailed among phospholipids. Mycolic acids were not detected. Based on the phenotypic, genomic and phylogenetic data, isolate A23^T represents a novel species of the genus Amycolatopsis, for which the name Amycolatopsis camponoti sp. nov. is proposed, and the type strain is A23^T (=?DSM 111725^T?=?VKM Ac-2882^T).

     

Correction to: Amycolatopsis camponoti sp. nov., new tetracenomycin-producing actinomycete isolated from carpenter ant Camponotus vagus

Antonie van Leeuwenhoek -     

Acidophilic Soil Actinomycetes

A clear-cut dependence of the distribution of acidophilic actinomycetes on the pH value of soil was established. Acidophilic actinomycetes were found to be present in soils whose pH does not exceed 6.8 (acid forest soils, lowland peaty soil, and ordinary chernozem) and not in slightly alkaline soils (chestnut sodic and alluvial meadow soils). In acid lowland peaty soil, the species diversity of acidophilic streptomycetes was lesser than the species diversity of streptomycetes revealed in the same soil by using neutral medium.     

Comparative study of actinomycete communities associated with Lasius niger and Formica cunicularia ants and their nests

A comparative analysis of the abundance and biodiversity of actinomycete communities isolated from living ants Lasius niger and Formica cunicularia, as well as their anthills, has been carried out for the first time. The number of actinomycetes detected in L. niger ants is close to the number of actinomycetes in their anthills and one order is higher than that for F. cunicularia. Actinomycete communities of anthills and the intact soil are characterized by a high diversity, equitability, absence of severe dominants, and the presence of common species and differ by number and the range of species. Biodiversity of actinomycetes associated with living ants is considerably lower than in their nests and the surrounding soil and the range of actinomycetes is specific for both the species of ants.     

Microbiological characteristic of anthills of <Emphasis Type="Italic">Lasius niger</Emphasis>

The characteristics of microbial communities of the anthills of Lasius niger compared to the soil beyond the area of the strong effect of ants is given.