Glushakova Anna, Sharova Anna, Kachalkin Aleksey
Soil Science Faculty, M.V. Lomonosov Moscow State University, 119991 Moscow, Russia.
I.I. Mechnikov Research Institute of Vaccines and Sera, 105064 Moscow, Russia.
J Fungi (Basel). 2024 Jul 30;10(8):532. doi: 10.3390/jof10080532.
The culturable yeast communities in temperate forest soils under the ornithogenic influence were studied in a seasonal dynamic. To investigate the intense ornithogenic influence, conventional and "live" feeders were used, which were attached to trees in the forest and constantly replenished throughout the year. It was found that the yeast abundance in the soil under strong ornithogenic influence reached the highest values in winter compared to the other seasons and amounted to 4.8 lg (cfu/g). This was almost an order of magnitude higher than the minimum value of yeast abundance in ornithogenic soils determined for summer. A total of 44 yeast species, 21 ascomycetes and 23 basidiomycetes, were detected in ornithogenic soil samples during the year. These included soil-related species (, , , , , , , , , , , and ), eurybionts (yeast-like fungus , , and ), inhabitants of plant substrates and litter (, , , , , , and ) as well as a group of pathogenic and opportunistic yeast species (, , , , , and ). Under an ornithogenic influence, the diversity of soil yeasts was higher compared to the control, confirming the uneven distribution of yeasts in temperate forest soils and their dependence on natural hosts and vectors. Interestingly, the absolute dominant species in ornithogenic soils in winter (when the topsoil temperature was below zero) was the basidiomycetous psychrotolerant yeast . It is regularly observed in various soils in different geographical regions. Screening of the hydrolytic activity of 50 strains of this species at different temperatures (2, 4, 10, 15 and 20 °C) showed that the activity of esterases, lipases and proteases was significantly higher at the cultivation temperature. Ornithogenic soils could be a source for the relatively easy isolation of a large number of strains of the psychrotolerant yeast to test, study and optimize their potential for the production of cold-adapted enzymes for industry.
对受鸟类活动影响的温带森林土壤中可培养酵母群落进行了季节性动态研究。为了研究强烈的鸟类活动影响，使用了传统的和“活的”喂食器，将它们附着在森林中的树木上，并全年不断补充食物。结果发现，与其他季节相比，受强烈鸟类活动影响的土壤中酵母丰度在冬季达到最高值，为4.8 lg（cfu/g）。这几乎比夏季测定的受鸟类活动影响土壤中酵母丰度的最小值高一个数量级。在一年中，受鸟类活动影响的土壤样本中共检测到44种酵母，其中21种为子囊菌，23种为担子菌。这些包括与土壤相关的物种（、、、、、、、、、、、和）、广适生物（类酵母真菌、、和）、植物基质和凋落物的栖息者（、、、、、、和）以及一组致病和机会性酵母物种（、、、、、和）。在鸟类活动影响下，土壤酵母的多样性高于对照，这证实了酵母在温带森林土壤中的分布不均及其对天然宿主和传播媒介的依赖性。有趣的是，冬季（表土温度低于零摄氏度）受鸟类活动影响的土壤中的绝对优势种是担子菌耐冷酵母。它经常在不同地理区域的各种土壤中被观察到。对该物种的50个菌株在不同温度（2、4、10、15和20℃）下的水解活性进行筛选，结果表明，酯酶、脂肪酶和蛋白酶的活性在培养温度下显著更高。受鸟类活动影响的土壤可能是相对容易分离出大量耐冷酵母菌株的来源，以便测试、研究和优化它们生产工业用低温适应酶的潜力。
