Water-soluble phenolic compounds in lichens

The quantity and the qualitative composition (for some species) of phenolic compounds (PC) washed out of the intact thalli of lichens of the orders Peltigerales (the genera Peltigera, Solorina, and Nephroma) and Lecanorales (the genera Cladonia, Alectoria, and Cetraria) were studied. It was shown that the quantity of leachable PCs in Peltigerales was on average 2–3 times higher than in Lecanorales. At the same time, the extractability of PC from intact thalli by water was higher in Lecanorales than in Peltigerales: 48–88% and 34–70%, respectively, of the PC content in ethanol extracts from crushed thalli (i.e., of the total content of soluble PC). Water-soluble PC in the lichens Peltigera aphthosa, Solorina crocea, Cetraria islandica, Flavocetraria nivalis, Cladonia uncialis, and Cladonia arbuscula were represented by 7–12 phenolic compounds with similar qualitative composition in the species of the same order. The most part of water soluble PC were phenylpropanoids. All of the studied species showed the presence of p-hydroxybenzoic acid derivatives; vanillic and protocatechuic acid derivatives were found in Cetraria and Cladonia species, respectively.     

Methanocalculus natronophilus sp. nov., a new alkaliphilic hydrogenotrophic methanogenic archaeon from a soda lake,and proposal of the new family Methanocalculaceae

A mesophilic hydrogenotrophic methanogenic archaeon, strain Z-7105^T, was isolated from the bottom sediments of a collector in the vicinity of a soda lake Tanatar II (Altai, Russia). The cells were motile, irregular cocci 0.2–1.2 μm in diameter. The organism was an obligate alkaliphile, growing within a pH range from 8.0 to 10.2, with the optimum at pH 9.0–9.5. It was obligately dependent on carbonates, growing at 0.5 to 1.6 M total carbonates with the optimum at 0.7–0.9 M. Sodium ions were also obligately required at concentrations from 0.9 to 3.3 M Na⁺ (optimum at 1.4–1.9 M). The organism was halotolerant, but Clions were not required. Hydrogen and formate were used as electron donors. Acetate was required for anabolism. The DNA G+C content was 50.2 mol %. According to the results of its 16S rRNA gene sequence analysis, the isolate belonged to the genus Methanocalculus, being the first known alkaliphilic member of this genus. Its similarity to the neutrophilic and halotolerant Methanocalculus species (M. halotolerans, M. taiwanensis, M. pumilus, and M. chunghsingensis) was 98.2–97.1%, which is within the interspecific range for this genus. The level of DNA-DNA hybridization between strain Z-7105^T and the Methanocalculus type species M. halotolerans DSM 14092^T was 32%. The genus Methanocalculus, including the new isolate and the previously described species, is distant from other genera of methanogens (<90% 16S rRNA gene similarity). Based on significant phenotypic differences and the results of phylogenetic analysis, including DNA-DNA hybridization, it is proposed to assign strain Z-7105^T (=DSM 25006^T, =VKM B-2765^T) to the new species Methanocalculus natronophilus sp. nov., and to incorporate the genus into the new family Methanocalculaceae fam. nov.     

Effect of pineal peptide on parameters of the biological age and life span in mice

Female CBA mice were injected with s.c. synthetic tetrapeptide Epithalon from a 6-month age until death. The drug failed to affect the body weight or food consumption, physical activity or behavioural parameters. However, it slowed down the age-related switching off of the estrus function, decreased body temperature, decelerated free redical processes, prolonged the mice life span with an accompanying drop in spontaneous tumour incidence.     

Erratum to: Deferrivibrio essentukiensis gen. nov., sp. nov., a Representative of Deferrivibrionaceae fam. nov., Isolated from the Subsurface Aquifer of Caucasian Mineral Drinking Waters

Microbiology - An Erratum to this paper has been published: https://doi.org/10.1134/S0026261722700011     

Reduction of synthetic ferrihydrite by a binary anaerobic culture of <Emphasis Type="Italic">Anaerobacillus alkalilacustris</Emphasis> and <Emphasis Type="Italic">Geoalkalibacter ferrihydriticus</Emphasis> grown on mannitol at pH 9.5

In the course of an investigation of alkaliphilic iron reduction, metabiotic interactions in a binary culture reducing synthetic ferrihydrite (SF) have been studied. The binary culture contained two anaerobic bacteria: the alkaliphilic organotrophic bacillus Anaerobacillus alkalilacustris, which ferments sugars and sugar alcohols and is incapable of iron reduction, and the dissimilatory iron-reducing bacterium Geoalkalibacter ferrihydriticus, which is able to grow on acetate at the expense of anaerobic respiration. The experiments were performed under conditions of SF excess and deficiency. It was expected that G. ferrihydriticus would oxidize the acetate formed in the course of mannitol fermentation by A. alkalilacustris. The results were different from the expected ones: in the binary culture, fermentation products other than acetate were used for iron reduction; these were primarily formate and ethanol, which led to acetate accumulation rather than consumption. The reduction of SF to magnetite and/or siderite followed the earlier established regularities. The preferential order of donor utilization by G. ferrihydriticus did not conform to the energy yields of the corresponding reactions. Thus, it has been shown that there may be interactions in microbial communities that cannot be predicted from the characteristics of pure cultures. The degradation pathways of organic matter in communities may differ considerably from those observed in pure cultures, even in pure cultures of highly specialized organisms.     

Laccase Production and Humic Acids Decomposition by Microscopic Soil Fungi

Laccase (para-diphenol:oxygen oxidoreductase, EC 1.10.3.2) is a phenol oxidase widespread in fungi and bacteria. In basidiomycetes, this enzyme is involved in the transformation of lignin and humic substances (HS) in soil. The role of laccases of soil ascomycetes and deuteromycetes in HS degradation is not established, and conditions of the enzyme production have been poorly studied. In the present work soil micromycetes, potential laccase producers, were isolated from typical soils of the forest, steppe, and foreststeppe zones of European Russia by plating on agar media with ABTS (2,2'-azino-bis(3-ethylbenzothiazoline- 6-sulphonic acid, sodium salt)) as the substrate. Their abundance, species composition, conditions of laccase production, and its relation to humic acids (HA) degradation in liquid and solid media were studied. Out of 68 strains isolated, 20 exhibited ABTS oxidation at initial plating on agar media. In pure cultures on agar media, oxidation was less pronounced, but in the presence of HA laccase production by some strains was higher than without HA. Significant and weak extracellular laccase production in liquid medium was observed for Acremonium murorum (Corda) W. Gams Z1710 and Botritis cinerea Pers. ex Fries Z1711, respectively. The level of laccase production by A. murorum was the same without inducers and in the presence of HA, while B. cinerea produced laccase only without inducers. No direct correlation was found between the presence of laccase and/or its activity and ability of the fungi to decolorize (degrade) HA. In liquid media active laccase producer A. murorum caused lower HA decolorization (43%) than B. cinerea (62%) and the fungi lacking extracellular laccase (54–81%). The role of micromycete oxidative systems in HA degradation requires further investigation.     

Erratum to: Deferrivibrio essentukiensis sp. nov., gen. nov., a Representative of Deferrivibrionaceae fam. nov., Isolated from the Subsurface Aquifer of Caucasian Mineral Drinking Waters

Microbiology - An Erratum to this paper has been published: https://doi.org/10.1134/S002626172213001X     

<Emphasis Type="Italic">Thermincola ferriacetica</Emphasis> sp. nov<Emphasis Type="Italic">.,</Emphasis> a new anaerobic,thermophilic, facultatively chemolithoautotrophic bacterium capable of dissimilatory Fe(III) reduction

A moderately thermophilic, sporeforming bacterium able to reduce amorphous Fe(III)-hydroxide was isolated from ferric deposits of a terrestrial hydrothermal spring, Kunashir Island (Kurils), and designated as strain Z-0001. Cells of strain Z-0001 were straight, Gram-positive rods, slowly motile. Strain Z-0001 was found to be an obligate anaerobe. It grew in the temperature range from 45 to 70°C with an optimum at 57–60°C, in a pH range from 5.9 to 8.0 with an optimum at 7.0–7.2, and in NaCl concentration range 0–3.5% with an optimum at 0%. Molecular hydrogen, acetate, peptone, yeast and beef extracts, glycogen, glycolate, pyruvate, betaine, choline, N-acetyl-d-glucosamine and casamino acids were used as energy substrates for growth in presence of Fe(III) as an electron acceptor. Sugars did not support growth. Magnetite, Mn(IV) and anthraquinone-2,6-disulfonate served as the alternative electron acceptors, supporting the growth of isolate Z-0001 with acetate as electron donor. Formation of magnetite was observed when amorphous Fe(III) hydroxide was used as electron acceptor. Yeast extract, if added, stimulated growth, but was not required. Isolate Z-0001 was able to grow chemolithoautotrophicaly with molecular hydrogen as the only energy substrate, Fe(III) as electron acceptor and CO₂ as the carbon source. Isolate Z-0001 was able to grow with 100% CO as the sole energy source, producing H₂ and CO₂, requiring the presence of 0.2 g l⁻¹ of acetate as the carbon source. The G+C content of strain Z-0001^T DNA G+C was 47.8 mol%. Based on 16S rRNA sequence analyses strain Z-0001 fell into the cluster of family Peptococcaceae, within the low G+C content Gram-Positive bacteria, clustering with Thermincola carboxydophila (98% similarity). DNA–DNA hybridization with T. carboxydophila was 27%. On the basis of physiological and phylogenetic data it is proposed that strain Z-0001^T (=DSMZ 14005, VKM B-2307) should be placed in the genus Thermincola as a new species Thermincola ferriacetica sp. nov. The GenBank accession number for the sequence reported in the paper is AY 631277.     

<Emphasis Type="Italic">Alkaliphilus peptidofermentans</Emphasis> sp. nov., a new alkaliphilic bacterial soda lake isolate capable of peptide fermentation and Fe(III) reduction

A novel strain, Z-7036, of anaerobic spore-forming bacteria was isolated from a cellulolytic consortium obtained from the bottom sediments of the low-mineralization soda lake Verkhnee Beloe (Buryatia). The cells of the new strain are short motile gram-positive rods, 1.1–3.0 × 0.25–0.4 μm. The organism is an aerotolerant anaerobe and obligate alkaliphile growing within the pH range of 7.5–9.7 with an optimum at pH 9.1. The strain is mesophilic and halotolerant and grows at NaCl concentrations from 0 to 50 g/l with an optimum at 20 g/l. Carbonates are required. The microorganism ferments peptone, yeast extract, trypticase, tryptone, Bacto Soytone, meat extract, Casamino acids, ornithine, arginine, threonine, and tryptophan. The strain hydrolyzes the bacterial preparations “Gaprin” and “Spirulina”. Acetate and formate are the major fermentation products. The strain reduces amorphous ferric hydroxide (AFH), EDTA-Fe(III), anthraquinone-2,6-disulfonate (quinone), S₂O ₃ ^2? , fumarate, and crotonate. Major fatty acids are C_16:0, C1_6:1ω7c, iso-C₁₇, iso-C₁₅, and iso-C_17:1. The DNA G+C content is 33.8 ± 0.5 mol %. According to the results of the 16S rRNA gene analysis, strain Z-7036 belongs to the genus Alkaliphilus within the cluster XI of low G+C gram-positive bacteria of the family Clostridiaceae. The novel strain is closely related to A. transvaalensis SAGM1^T and A. crotonatoxidans B11-2^T (93.3 and 93.9% 16S rRNA sequence identities, respectively). On the basis of the existing genotypic and phenotypic differences, we propose that strain Z-7036 should be classified as a novel species Alkaliphilus peptidofermentans sp. nov.