Global warming due to climate change has substantial impact on high-altitude permafrost affected soils. This raises a serious concern that the microbial degradation of sequestered carbon can result in alteration of the biogeochemical cycles. Therefore, the characterization of permafrost affected soil microbiomes, especially of unexplored high-altitude, low oxygen arid region, is important for predicting their response to climate change. This study presents the first report of the bacterial diversity of permafrost-affected soils in the Changthang region of Ladakh. The relationship between soil pH, organic carbon, electrical conductivity, and available micronutrients with the microbial diversity was investigated. Amplicon sequencing of permafrost affected soil samples from Jukti and Tsokar showed that Proteobacteria and Actinobacteria were the dominant phyla in all samples. The genera Brevitalea, Chthoniobacter, Sphingomonas, Hydrogenispora, Clostridium, Gaiella, Gemmatimonas were relatively abundant in the Jukti samples whereas the genera Thiocapsa, Actinotalea, Syntrophotalea, Antracticibcterium, Luteolibacter, Nitrospirillum dominated the Tsokar sample. Correlation analyses highlighted the influence of soil geochemical parameters on the bacterial community structure. PCoA analyses showed that the bacterial beta diversity varied significantly between the sampling locations (PERMANOVA test (F-value: 2.3316; R2 = 0.466, p = 0.001) and similar results were also obtained while comparing genus abundance data using the ANOSIM test (R = 0.345, p = 0.007).
White grubs are known as the National pest of India due to their wide distribution and economic damage. Brahmina coriacea grubs are restricted to Tibet, China and the Himalayan region in Jammu and Kashmir, Himachal Pradesh and Uttarakhand. The grubs of B. coriacea were collected from the soil of Solanum tuberosum, Zea mays, Pisum sativum, Rosa rubiginosa, Phaseolus vulgaris, Malus pumila and Pyrus communis from different ecosystems of eight different locations in Himachal Pradesh, India, by the pit sampling method. The grubs of B. coriacea were identified by examining the raster pattern. There was variation in the morphology and biology among different populations of B. coriacea in Himachal Pradesh. The morphological parameters and biological differences were also recorded, such as fecundity rate and damage potential among different ecotypes of B. coriacea collected from various locations. A total of 102 morphologically distinct bacterial isolates were isolated from the gut of different populations of B. coriacea. The gut microbial diversity and abundance were recorded as maximum in the hind gut, compared to other gut compartments. A total of 11 cellulolytic bacterial isolates were identified using morphological, biochemical and 16S rRNA molecular methods. The cellulolytic index of bacterial strains ranged from 0.33 to 2.0. The 11 gut cellulolytic bacteria were identified by using morphological, biochemical and 16S rRNA gene analysis. Staphylococcus haemolyticus was isolated from the Nauni population of B. coriacea, and it is the first report from the gut of scarabaeids. This is an opportunistic human pathogen but a useful endosymbiont in the grubs of B. coriacea. Bacillus thuringiensis as a biological agent, Staphylococcus cohnii, Ralstonia mannitolilytica and some Bacillus sp. were reported for the first time from B. coriacea grubs in India. The potent cellulose-degrading bacteria can be used in industries for decomposing agricultural waste, in pulp and paper industries and for biofuel production.
Acid sulfate soils impact surrounding ecosystems with pronounced environmental damage via leaching of strong acidity along with the concurrent mobilization of toxic metals present in the soils and, in consequence, they are often described as the nastiest soils on Earth. Within Sweden, acid sulfate soils are distributed mainly under the maximum Holocene marine limit that stretches the length of the country, some 2000 km north to south. Despite only minor geographical differences in the geochemical composition of the Swedish acid sulfate soils, their field oxidation zone microbial community compositions differ along a north-south regional divide. This study compared the 16S rRNA gene amplicon-based microbial community compositions of field oxidation zones (field tested pH 6.5) collected from the same field sites throughout Sweden that had acidified (final pH = 20 degrees C) greater than what was experienced by the field oxidation zone samples when sampled (similar to 2 degrees C-9 degrees C). These data suggested that in the absence of significant geochemical differences, temperature was the predominant driver of microbial community composition in Swedish acid sulfate soil materials.
A Gram-stain-positive, facultatively anaerobic, rod-shaped bacterium, designated JX-17(T), was isolated from a soil sample collected in Jiangxi Province, PR China. Growth was observed at 15-48(degrees)C (optimum 37 C-degrees), at pH 5.0-9.0 (optimum pH 7.0) and with 0-6.0% (w/v) NaCl (optimum 1.0%). Strain JX-17(T) could degrade approximately 50% of 50 mg/L mesotrione within 2 days of incubation, but could not use mesotrione as sole carbon source for growth. Strain JX-17(T) showed less than 95.3% 16S rRNA gene sequence similarity with type strains of the genus Paenibacillus. In the phylogenetic tree based on 16S rRNA gene and genome sequences, strain JX-17(T) formed a distinct lineage within the genus Paenibacillus. The ANI values between JX-17(T) and the most closely related type strains P. lentus CMG1240(T) and P. farraposensis UY79(T) were 70.1% and 71.4%, respectively, and the dDDH values between them were 19.0% and 23.3%, respectively. The major cellular fatty acids were anteiso-C-15:0, iso-C-16:0, anteiso-C-17:0 and C-16:0, the predominant respiratory quinone was MK-7, the major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, an unidentified glycolipid, an aminophospholipid and a phosphatidylinositol. The diagnostic diamino acid of the peptidoglycan was meso-diaminopimelic acid, and the DNA G + C content was 50.1 mol%. Based on the phylogenetic, phenotypic and chemotaxonomic characteristics, strain JX-17(T) represents a novel species within the genus Paenibacillus, for which the name Paenibacillus lacisoli sp. nov is proposed, with strain JX-17(T) (= GDMCC 1.3962(T) = KCTC 43568(T)) as the type strain.
Root-knot nematodes (RKNs) of the genus Meloidogyne are one of the most damaging genera to cultivated woody plants with a worldwide distribution. The knowledge of the soil and rhizosphere microbiota of almonds infested with Meloidogyne could help to establish new sustainable and efficient management strategies. However, the soil microbiota interaction in deciduous woody plants infected with RKNs is scarcely studied. This research was carried out in six commercial almond groves located in southern Spain and infested with different levels of Meloidogyne spp. within each grove. Several parameters were measured: nematode assemblages, levels and biocontrol agents in Meloidogyne's eggs, levels of specific biocontrol agents in rhizoplane and soil, levels of bacteria and fungi in rhizoplane and soil, fungal and bacterial communities by high-throughput sequencing of internal transcribed spacer (ITS), and 16S rRNA gene in soil and rhizosphere of the susceptible almond hybrid rootstock GF-677 infested with Meloidogyne spp. The studied almond groves showed soil degradation by nematode assemblies and fungi:bacterial ratio. Fungal parasites of Meloidogyne eggs were found in 56.25% of the samples. However, the percentage of parasitized eggs by fungi ranged from 1% to 8%. Three fungal species were isolated from Meloidogyne eggs, specifically Pochonia chlamydosporia, Purpureocillium lilacinum, and Trichoderma asperellum. The diversity and composition of the microbial communities were more affected by the sample type (soil vs rhizosphere) and by the geographical location of the samples than by the Meloidogyne density, which could be explained by the vigorous hybrid rootstock GF-677 and a possible dilution effect. However, the saprotrophic function in the functional guilds of the fungal ASV was increased in the highly infected roots vs the low infected roots. These results indicate that the presence of biocontrol agents in almond fields and the development of new management strategies could increase their populations to control partially RKN infection levels.
The active layer is the portion of soil overlaying the permafrost that freezes and thaws seasonally. It is a harsh habitat in which a varied and vigorous microbial population thrives. The high-altitude active layer soil in northern India is a unique and important cryo-ecosystem. However, its microbiology remains largely unexplored. It represents a unique reservoir for microbial communities with adaptability to harsh environmental conditions. In the Changthang region of Ladakh, the Tsokar area is a high-altitude permafrost-affected area situated in the southern part of Ladakh, at a height of 4530 m above sea level. Results of the comparison study with the QTP, Himalayan, Alaskan, Russian, Canadian and Polar active layers showed that the alpha diversity was significantly higher in the Ladakh and QTP active layers as the environmental condition of both the sites were similar. Moreover, the sampling site in the Ladakh region was in a thawing condition at the time of sampling which possibly provided nutrients and access to alternative nitrogen and carbon sources to the microorganisms thriving in it. Analysis of the samples suggested that the geochemical parameters and environmental conditions shape the microbial alpha diversity and community composition. Further analysis revealed that the cold-adapted methanogens were present in the Ladakh, Himalayan, Polar and Alaskan samples and absent in QTP, Russian and Canadian active layer samples. These methanogens could produce methane at slow rates in the active layer soils that could increase the atmospheric temperature owing to climate change.
Actinobacteria are abundant in soil and other environmental ecosystems and are also an important part of the human microbiota. Hence, they can also be detected in indoor environments and on building materials, where actinobacterial proliferation on damp materials can indicate moisture damage. The aim of this study was to evaluate the matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) for the identification of 28 environmental strains of Actinobacteria isolated from building materials and indoor and outdoor air samples, mainly collected in the context of moisture damage investigations in buildings in Finland. The 16S rRNA gene sequencing and chemotaxonomic analyses were performed, and results were compared with the MALDI-TOF MS Biotyper identification. Using 16S rRNA gene sequencing, all isolates were identified on the species or genus level and were representatives of Streptomyces, Nocardia, and Pseudonocardia genera. Based on MALDI-TOF MS analysis, initially, 11 isolates were identified as Streptomyces spp. and 1 as Nocardia carnea with a high identification score. After an upgrade in the MALDI-TOF MS in-house database and re-evaluation of mass spectra, 13 additional isolates were identified as Nocardia, Pseudonocardia, and Streptomyces. MALDI-TOF MS has the potential in environmental strain identification; however, the standard database needs to be considerably enriched by environmental Actinobacteria representatives.IMPORTANCEThe manuscript addresses the challenges in identifying environmental bacteria using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) Biotyper-based protein profiling. The matter of the studies-actinobacterial strains-has been isolated mostly from building materials that originated from a confirmed moisture-damaged situation. Polyphasic taxonomy, 16S RNA gene sequencing, and MALDI-TOF mass spectrometry were applied for identification purposes. In this experimental paper, a few important facts are highlighted. First, Actinobacteria are abundant in the natural as well as built environment, and their identification on the species and genus levels is difficult and time-consuming. Second, MALDI-TOF MS is an effective tool for identifying bacterial environmental strains, and in parallel, continuous enrichment of the proteomics mass spectral databases is necessary for proper identification. Third, the chemical approach aids in the taxonomical inquiry of Actinobacteria environmental strains. The manuscript addresses the challenges in identifying environmental bacteria using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) Biotyper-based protein profiling. The matter of the studies-actinobacterial strains-has been isolated mostly from building materials that originated from a confirmed moisture-damaged situation. Polyphasic taxonomy, 16S RNA gene sequencing, and MALDI-TOF mass spectrometry were applied for identification purposes. In this experimental paper, a few important facts are highlighted. First, Actinobacteria are abundant in the natural as well as built environment, and their identification on the species and genus levels is difficult and time-consuming. Second, MALDI-TOF MS is an effective tool for identifying bacterial environmental strains, and in parallel, continuous enrichment of the proteomics mass spectral databases is necessary for proper identification. Third, the chemical approach aids in the taxonomical inquiry of Actinobacteria environmental strains.
植物内生菌(Endophyte)在宿主植物组织中的分布规律是内生菌对外界适应的重要机制。基于Illumina MiSeq测序技术,对适应青藏高原极端环境的主要疯草植物—冰川棘豆叶和根组织中的内生菌16S rRNA、ITS rDNA进行高通量测序和生物信息学分析,通过明晰内生菌在冰川棘豆组织中的菌群结构、功能以及环境之间的关系,探讨了组织间内生菌的分布特征对冰川棘豆适应极端环境的可能影响。分析结果表明,冰川棘豆组织间共有菌属丰度占菌属总丰度90%以上,不同组织间形成了保守性内生细菌和特异性内生真菌共存的群落结构特点,植物组织结构和环境的影响可能为推动内生菌选择合适的组织生态位定植提供动力,其中土壤含水量显著影响内生细菌(R2=0.241,P=0.024)和内生真菌(R2=0.223,P=0.031)的组间Beta多样性,土壤pH值显著影响内生真菌(R2=0.571,P<0.001)Alpha多样性丰富度指数,而环境因素对组织间存在显著差异的内生菌功能和营养型解释并不显著。综合认为,保守性与差异性的内生菌菌群结构和功能...
植物内生菌(Endophyte)在宿主植物组织中的分布规律是内生菌对外界适应的重要机制。基于Illumina MiSeq测序技术,对适应青藏高原极端环境的主要疯草植物—冰川棘豆叶和根组织中的内生菌16S rRNA、ITS rDNA进行高通量测序和生物信息学分析,通过明晰内生菌在冰川棘豆组织中的菌群结构、功能以及环境之间的关系,探讨了组织间内生菌的分布特征对冰川棘豆适应极端环境的可能影响。分析结果表明,冰川棘豆组织间共有菌属丰度占菌属总丰度90%以上,不同组织间形成了保守性内生细菌和特异性内生真菌共存的群落结构特点,植物组织结构和环境的影响可能为推动内生菌选择合适的组织生态位定植提供动力,其中土壤含水量显著影响内生细菌(R2=0.241,P=0.024)和内生真菌(R2=0.223,P=0.031)的组间Beta多样性,土壤pH值显著影响内生真菌(R2=0.571,P<0.001)Alpha多样性丰富度指数,而环境因素对组织间存在显著差异的内生菌功能和营养型解释并不显著。综合认为,保守性与差异性的内生菌菌群结构和功能...
植物内生菌(Endophyte)在宿主植物组织中的分布规律是内生菌对外界适应的重要机制。基于Illumina MiSeq测序技术,对适应青藏高原极端环境的主要疯草植物—冰川棘豆叶和根组织中的内生菌16S rRNA、ITS rDNA进行高通量测序和生物信息学分析,通过明晰内生菌在冰川棘豆组织中的菌群结构、功能以及环境之间的关系,探讨了组织间内生菌的分布特征对冰川棘豆适应极端环境的可能影响。分析结果表明,冰川棘豆组织间共有菌属丰度占菌属总丰度90%以上,不同组织间形成了保守性内生细菌和特异性内生真菌共存的群落结构特点,植物组织结构和环境的影响可能为推动内生菌选择合适的组织生态位定植提供动力,其中土壤含水量显著影响内生细菌(R2=0.241,P=0.024)和内生真菌(R2=0.223,P=0.031)的组间Beta多样性,土壤pH值显著影响内生真菌(R2=0.571,P<0.001)Alpha多样性丰富度指数,而环境因素对组织间存在显著差异的内生菌功能和营养型解释并不显著。综合认为,保守性与差异性的内生菌菌群结构和功能...