RESUMEN
Seven novel independent strains of Mycoplasma species were isolated from northern elephant seals (ES2806-NAST, ES2806-GENT, ES3157-GEN-MYC and ES3225-GEN-MYC), a harbour porpoise (C264-GENT and C264-NAST), and a California sea lion (CSL7498). These strains were phenotypically and genetically characterized and compared to the known Mycoplasma species. Four strains (C264-GENT, C264-NAST, CSL7498 and ES2806-NAST) hydrolysed arginine but not urea and did not produce acid from carbohydrates. Strains ES2806-GENT, ES3157-GEN-MYC and ES3225-GEN-MYC did not produced acid from carbohydrates and did not hydrolyse arginine or urea; hence, it is assumed that organic acids are used as the energy source for them. All were isolated and propagated in ambient air supplemented with 5±1â% CO2 at +35-37 °C using either SP4 or PPLO medium. Colonies on solid medium showed a typical fried-egg appearance and transmission electron microscopy revealed a typical mycoplasma cellular morphology. The complete genomes were sequenced for all type strains. Average nucleotide and amino acid identity analyses showed that these novel strains were distant from the phylogenetically closely related Mycoplasma species. Based on these data, we propose four novel species of the genus Mycoplasma, for which the name Mycoplasma miroungirhinis sp. nov. is proposed with the type strain ES2806-NAST (=NCTC 14430T=DSM 110945T), Mycoplasma miroungigenitalium sp. nov. is proposed with the type strain ES2806-GENT (=NCTC 14429T=DSM 110944T) and representative strains ES3157-GEN-MYC and ES3225-GEN-MYC, Mycoplasma phocoenae sp. nov. is proposed with the type strain C264-GENT (=NCTC 14344T=DSM 110687T) and Mycoplasma phocoeninasale sp. nov. is proposed with the type strain C264-NAST (=NCTC 14343T=DSM 110688T) and representative strain CSL7498. The genome G+C contents are 24.06, 30.09, 28.49 and 29.05% and the complete genome sizes are 779â550, 815â486, 693â115, and 776â009 bp for strains ES2806-NAST, ES2806-GENT, C264-GENT and C264-NAST, respectively.
Asunto(s)
Mycoplasma , Phocoena , Filogenia , Leones Marinos , Phocidae , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Mycoplasma/clasificación , Mycoplasma/aislamiento & purificación , Phocoena/microbiología , ARN Ribosómico 16S/genética , Leones Marinos/microbiología , Phocidae/microbiología , Análisis de Secuencia de ADNRESUMEN
Two independent strains of a Leptotrichia species (ES3154-GLUT and ES2714_GLU) were isolated from the oral cavity of northern elephant seals (Mirounga angustirostris) that were admitted to The Marine Mammal Centre facilities in California, USA. The strains were isolated from oral swabs by cultivation in PPLO broth supplemented with serum, penicillin and colistin in anaerobic conditions. The strains were Gram-negative, pleomorphic, indole-, oxidase- and catalase-negative, non-spore-forming, non-motile rods/coccobacilli in short chains. The 16S rRNA gene sequence of these strains shared 94.42â% nucleotide similarity with Oceanivirga salmonicida AVG 2115T but demonstrated ≤86.00-92.50â% nucleotide similarity to the 16S rRNA genes of other species of the family Leptotrichiaceae. The genome was sequenced for strain ES3154-GLUT. Average nucleotide identity values between strain ES3154-GLUT and 15 type strain genomes from the family Leptotrichiaceae ranged from 66.74â% vs. Sebaldella termitidis to 73.35â% vs. O. salmonicida. The whole genome phylogeny revealed that the novel species was most closely related to O. salmonicida AVG 2115T. This relationship was also confirmed by nucleotide similarity and multilocus phylogenetic analyses employing various housekeeping genes (partial 23S rRNA, rpoB, rpoC, rpoD, polC, adh, gyrA and gyrB genes). Chemotaxonomic and phenotypical features of strain ES3154-GLUT were in congruence with closely related members of the family Leptotrichiaceae, represented by similar enzyme profiles and fatty acid patterns. MALDI-TOF MS analysis was capable to clearly discriminate strain ES3154-GLUT from all currently described taxa of the family Leptotrichiaceae. Based on these data, we propose a novel species of the genus Oceanivirga, for which the name Oceanivirga miroungae sp. nov. is proposed with the type strain ES3154-GLUT (=DSM 109740T=CCUG 73653T=ATCC TSD-189T=NCTC 14411T) and one representative strain ES2714_GLU. The G+C content is 26.82 %, genome size is 1 356 983 bp.
Asunto(s)
Fusobacterias/clasificación , Boca/microbiología , Filogenia , Phocidae/microbiología , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , California , ADN Bacteriano/genética , Ácidos Grasos/química , Fusobacterias/aislamiento & purificación , Genes Bacterianos , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , ARN Ribosómico 23S , Análisis de Secuencia de ADNRESUMEN
Many representatives of the Bacillus subtilis species complex are known as plant growth-promoting rhizobacteria (PGPR) and are widely used in agriculture as biofertilizers and biocontrol agents. Two bacterial strains, "Korea isolate" and ZL918, taxonomically classified as being Bacillus amyloliquefaciens, isolated from disease-damaged plant organs, were alleged to cause bacterial rot in starchy storage plant organs. The aim of this study was to elucidate whether these findings have consequences for the general use of beneficial Bacilli in agriculture. Whole genome sequencing revealed that the pathogenic ZL918 was a representative of Bacillus velezensis. B. velezensis FZB42 and other representatives of the B. subtilis species complex caused the same symptoms of bacterial rot only when injected inside of potato tubers and onion bulbs, but not when inoculated onto the surface of the storage organs. It seemed that the pathogenic effect was due to starch hydrolyzing activity that likely stimulates propagation of endophytic bacteria inside of starchy tissues. After removing the inherent microbiota via Co60 γ-ray irradiation, the storage organs inoculated by either FZB42 or purified α-amylase did not develop rot symptoms. Two opportunistic pathogens, Pantoea ananatis and Pantoea agglomerans, isolated from the rotted area, were shown to cause bacterial rot in x-ray treated potato tuber and onion starchy tissues when the proteobacteria were applied in high concentration. This suggests that opportunistic pathogenic bacteria residing inside of the starchy storage organ are the causal agents of bacterial soft rot disease in potato tubers and other starchy plant storage organs.
Asunto(s)
Bacillus subtilis/genética , Bacillus subtilis/patogenicidad , Desarrollo de la Planta , Enfermedades de las Plantas/microbiología , alfa-Amilasas/metabolismo , Bacillus subtilis/enzimología , Mutación , Cebollas/microbiología , Raíces de Plantas/microbiología , Proteobacteria/fisiología , Solanum tuberosum/microbiología , Secuenciación Completa del GenomaRESUMEN
Despite the recent advancements in culturomics, isolation of the majority of environmental microbiota performing critical ecosystem services, such as bioremediation of contaminants, remains elusive. Towards this end, we conducted a metagenomics-guided comparative assessment of soil microbial diversity and functions present in uraniferous soils relative to those that grew in diffusion chambers (DC) or microbial traps (MT), followed by isolation of uranium (U) resistant microbiota. Shotgun metagenomic analysis performed on the soils used to establish the DC/MT chambers revealed Proteobacterial phyla and Burkholderia genus to be the most abundant among bacteria. The chamber-associated growth conditions further increased their abundances relative to the soils. Ascomycota was the most abundant fungal phylum in the chambers relative to the soils, with Penicillium as the most dominant genus. Metagenomics-based taxonomic findings completely mirrored the taxonomic composition of the retrieved isolates such that the U-resistant bacteria and fungi mainly belonged to Burkholderia and Penicillium species, thus confirming that the chambers facilitated proliferation and subsequent isolation of specific microbiota with environmentally relevant functions. Furthermore, shotgun metagenomic analysis also revealed that the gene classes for carbohydrate metabolism, virulence, and respiration predominated with functions related to stress response, membrane transport, and metabolism of aromatic compounds were also identified, albeit at lower levels. Of major note was the successful isolation of a potentially novel Penicillium species using the MT approach, as evidenced by whole genome sequence analysis and comparative genomic analysis, thus enhancing our overall understanding on the uranium cycling microbiota within the tested uraniferous soils.
Asunto(s)
Microbiota/genética , Microbiología del Suelo , Uranio/toxicidad , Ascomicetos/genética , Ascomicetos/efectos de la radiación , Biodegradación Ambiental , Burkholderia/genética , Burkholderia/efectos de la radiación , Ecosistema , Pradera , Humanos , Metagenómica , Microbiota/efectos de la radiación , Penicillium/genética , Penicillium/efectos de la radiación , Ríos , Estados UnidosRESUMEN
Lettuce (Lactuca sativa, L.) is an important annual plant of the family Asteraceae (Compositae). The commercial lettuce cultivar Tizian has been used in various scientific studies investigating the interaction of the plant with phytopathogens or biological control agents. Here, we present the de novo draft genome sequencing and gene prediction for this specific cultivar derived from transcriptome sequence data. The assembled scaffolds amount to a size of 2.22â¯Gb. Based on RNAseq data, 31,112 transcript isoforms were identified. Functional predictions for these transcripts were determined within the GenDBE annotation platform. Comparison with the cv. Salinas reference genome revealed a high degree of sequence similarity on genome and transcriptome levels, with an average amino acid identity of 99%. Furthermore, it was observed that two large regions are either missing or are highly divergent within the cv. Tizian genome compared to cv. Salinas. One of these regions covers the major resistance complex 1 region of cv. Salinas. The cv. Tizian draft genome sequence provides a valuable resource for future functional and transcriptome analyses focused on this lettuce cultivar.
Asunto(s)
Genoma de Planta/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Lactuca/genética , Transcriptoma/genética , Resistencia a la Enfermedad/genética , Anotación de Secuencia Molecular , Enfermedades de las Plantas/genética , Secuenciación Completa del Genoma/métodosRESUMEN
The basidiomycetes fungus Rhizoctonia solani AG3 is responsible for black scurf disease on potato and occurs in each potato growing area world-wide. In this study, the draft genome sequence of the black scurf pathogen R. solani AG3-PT isolate Ben3 is presented. The genome sequence of R. solani AG3-PT isolate Ben3 consists of 1385 scaffolds. These scaffolds amount to a size of approx. 51 Mb. Considering coverage analyses of contigs, the size of the diploid genome was estimated to correspond to 116 Mb. Gene prediction by applying AUGUSTUS (3.2.1.) resulted in 12,567 identified genes. Based on automatic annotation using GenDBE, genes potentially encoding cellulases and enzymes involved in secondary metabolite synthesis were identified in the R. solani AG3-PT isolate Ben3 genome. Comparative analyses including the R. solani AG3 isolate Rhs1AP, also originating from potato, revealed first insights into core genes shared by both isolates and unique determinants of each isolate.
Asunto(s)
Genoma Fúngico/genética , Enfermedades de las Plantas/microbiología , Rhizoctonia/genética , Rhizoctonia/aislamiento & purificación , Secuencia de Bases , Mapeo Cromosómico , Análisis de Secuencia de ADN , Solanum tuberosum/microbiologíaRESUMEN
Abstract Geobacillus thermodenitrificans DSM 101594 was isolated as a producer of extracellular thermostable pectic polysaccharide degrading enzymes. The completely sequenced genome was 3.6 Mb in length with GC content of 48.86%. A number of genes encoding enzymatic active against the high molecular weight polysaccharides of potential biotechnological importance were identified in the genome.
Asunto(s)
Genoma Bacteriano , Genómica , Geobacillus/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Pectinas/metabolismo , Biología Computacional/métodos , Genómica/métodos , Geobacillus/metabolismo , Anotación de Secuencia MolecularRESUMEN
Geobacillus thermodenitrificans DSM 101594 was isolated as a producer of extracellular thermostable pectic polysaccharide degrading enzymes. The completely sequenced genome was 3.6Mb in length with GC content of 48.86%. A number of genes encoding enzymatic active against the high molecular weight polysaccharides of potential biotechnological importance were identified in the genome.
Asunto(s)
Genoma Bacteriano , Genómica , Geobacillus/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Biología Computacional/métodos , Genómica/métodos , Geobacillus/metabolismo , Anotación de Secuencia Molecular , Pectinas/metabolismoRESUMEN
BACKGROUND: Sugar beet (Beta vulgaris) is a crop cultivated for its high content in sugar, but it is vulnerable to many soil-borne pathogens. One of them is the basidiomycete Rhizoctonia solani. This fungal species has a compatibility system regulating hyphal fusions (anastomosis). Consequently, R. solani species are categorized in anastomosis groups (AGs). AG2-2IIIB isolates are most aggressive on sugar beet. In the present study, we report on the draft genome of R. solani AG2-2IIIB using the Illumina technology. Genome analysis, interpretation and comparative genomics of five sequenced R. solani isolates were carried out. RESULTS: The draft genome of R. solani AG2-2IIIB has an estimated size of 56.02 Mb. In addition, two normalized EST libraries were sequenced. In total 20,790 of 21,980 AG2-2IIIB isotigs (transcript isoforms) were mapped on the genome with more than 95 % sequence identity. The genome of R. solani AG2-2IIIB was predicted to harbor 11,897 genes and 4908 were found to be isolate-specific. R. solani AG2-2IIIB was predicted to contain 1142 putatively secreted proteins and 473 of them were found to be unique for this isolate. The R. solani AG2-2IIIB genome encodes a high number of carbohydrate active enzymes. The highest numbers were observed for the polysaccharide lyases family 1 (PL-1), glycoside hydrolase family 43 (GH-43) and carbohydrate estarase family 12 (CE-12). Transcription analysis of selected genes representing different enzyme clades revealed a mixed pattern of up- and down-regulation six days after infection on sugar beets featuring variable levels of resistance compared to mycelia of the fungus grown in vitro. CONCLUSIONS: The established R. solani AG2-2IIIB genome and EST sequences provide important information on the gene content, gene structure and transcriptional activity for this sugar beet pathogen. The enriched genomic platform provides an important platform to enhance our understanding of R. solani biology.