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1.
Agar and agarose have wide applications in food and pharmaceutical industries. Knowledge on the genome of red seaweeds that produce them is still lacking. To fill the gap in genome analyses of these red algae, we have sequenced the nuclear and organellar genomes of an agarophyte, Gracilaria changii. The partial nuclear genome sequence of G. changii has a total length of 35.8 Mb with 10,912 predicted protein coding sequences. Only 39.4% predicted proteins were found to have significant matches to protein sequences in SwissProt. The chloroplast genome of G. changii is 183,855 bp with a total of 201 open reading frames (ORFs), 29 tRNAs and 3 rRNAs predicted. Five genes: ssrA, leuC and leuD CP76_p173 (orf139) and pbsA were absent in the chloroplast genome of G. changii. The genome information is valuable in accelerating functional studies of individual genes and resolving evolutionary relationship of red seaweeds.  相似文献   

2.
Heimuer, Auricularia heimuer, is one of the most famous traditional Chinese foods and medicines, and it is the third most important cultivated mushroom worldwide. The aim of this study is to develop genomic resources for A. heimuer to furnish tools that can be used to study its secondary metabolite production capability, wood degradation ability and biosynthesis of polysaccharides. The genome was obtained from single spore mycelia of the strain Dai 13782 by using combined high-throughput Illumina HiSeq 4000 system with the PacBio RSII long-read sequencing platform. Functional annotation was accomplished by blasting protein sequences with different public available databases to obtain their corresponding annotations. It is 49.76 Mb in size with a N50 scaffold size of 1,350,668 bp and encodes 16,244 putative predicted genes. This is the first genome-scale assembly and annotation for A. heimuer, which is the third sequenced species in Auricularia.  相似文献   

3.
Microorganisms classified in to the Pseudomonas genus are a ubiquitous bacteria inhabiting variety of environmental niches and have been isolated from soil, sediment, water and different parts of higher organisms (plants and animals). Members of this genus are known for their metabolic versatility and are able to utilize different chemical compounds as a source of carbon, nitrogen or phosphorus, which makes them an interesting microorganism for bioremediation or bio-transformation. Moreover, Pseudomonas sp. has been described as a microorganism that can easily adapt to new environmental conditions due to its resistance to the presence of high concentrations of heavy metals or chemical pollution. Here we present the isolation and analysis of Pseudomonas silesiensis sp. nov. strain A3T isolated from peaty soil used in a biological wastewater treatment plant exploited by a pesticide packaging company. Phylogenetic MLSA analysis of 4 housekeeping genes (16S rRNA, gyrB, rpoD and rpoB), complete genome sequence comparison (ANIb, Tetranucleotide identity, digital DDH), FAME analysis, and other biochemical tests indicate the A3T strain (type strain PCM 2856T = DSM 103370T) differs significantly from the closest relative species and therefore represents a new species within the Pseudomonas genus. Moreover, bioinformatic analysis of the complete sequenced genome showed that it consists of 6,823,539 bp with a 59.58 mol% G + C content and does not contain any additional plasmids. Genome annotation predicted the presence of 6066 genes, of which 5875 are coding proteins and 96 are RNA genes.  相似文献   

4.
We studied the taxonomic position of six phenetically related strains of the genus Acinetobacter, which were recovered from hospital sewage in China and showed different patterns of resistance to clinically important antibiotics. Whole-genome sequencing of these strains and genus-wide phylogeny reconstruction based on a set of 107 Acinetobacter core genes indicated that they formed a separate and internally cohesive clade within the genus. The average nucleotide identity based on BLAST and digital DNA–DNA hybridization values between the six new genomes were 97.25–98.67% and 79.2–89.3%, respectively, whereas those between them and the genomes of the known species were ≤78.57% and ≤28.5%, respectively. The distinctness of the strains at the species level was also supported by the results of the cluster analysis of the whole-cell protein fingerprints generated by MALDI-TOF MS. Moreover, the strains displayed a catabolically unique profile and could be differentiated from the phylogenetically closest species at least by their inability to grow on d,l-lactate. A total of 18 different genes were found in the six genome sequences which encode resistance to seven classes of antimicrobial agents, including clinically important carbapenems, oxyimino-cephalosporins, or aminoglycosides. These genes occurred in five different combinations, with three to 10 different genes per strain. We conclude that the six strains represent a novel Acinetobacter species, for which we propose the name Acinetobacter cumulans sp. nov. to reflect its ability to acquire and cumulate diverse resistance determinants. The type strain is WCHAc060092T (ANC 5797T = CCTCC AB 2018119T = GDMCC 1.1380T = KCTC 62576T).  相似文献   

5.
Bacteria of the genus ‘Candidatus Phytoplasma’ are uncultivated intracellular plant pathogens transmitted by phloem-feeding insects. They have small genomes lacking genes for essential metabolites, which they acquire from either plant or insect hosts. Nonetheless, some phytoplasmas, such as ‘Ca. P. solani’, have broad plant host range and are transmitted by several polyphagous insect species. To understand better how these obligate symbionts can colonize such a wide range of hosts, the genome of ‘Ca. P. solani’ strain SA-1 was sequenced from infected periwinkle via a metagenomics approach. The de novo assembly generated a draft genome with 19 contigs totalling 821,322 bp, which corresponded to more than 80% of the estimated genome size. Further completion of the genome was challenging due to the high occurrence of repetitive sequences. The majority of repeats consisted of gene arrangements characteristic of phytoplasma potential mobile units (PMUs). These regions showed variation in gene orders intermixed with genes of unknown functions and lack of similarity to other phytoplasma genes, suggesting that they were prone to rearrangements and acquisition of new sequences via recombination. The availability of this high-quality draft genome also provided a foundation for genome-scale genotypic analysis (e.g., average nucleotide identity and average amino acid identity) and molecular phylogenetic analysis. Phylogenetic analyses provided evidence of horizontal transfer for PMU-like elements from various phytoplasmas, including distantly related ones. The ‘Ca. P. solani’ SA-1 genome also contained putative secreted protein/effector genes, including a homologue of SAP11, found in many other phytoplasma species.  相似文献   

6.
Herein, the complete mitochondrial genome of Odontobutis haifengensis was sequenced for the first time. The O. haifengensis mitogenome was 17,016 bp in length and included 13 protein-coding genes, 22 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs), and a control region (CR). The genome organization, base composition, codon usage, and gene rearrangement was similar to other Odontobutis species. Furthermore, a tRNA gene rearrangement within the SLH cluster was found to be identical to other Odontobutis species. Moreover, the gene order and the positions of additional intergenic non-coding regions suggests that the observed unique gene rearrangement resulted from a tandem duplication and random loss of large-scale gene regions. Additionally, phylogenetic analysis showed that Odontobutis species form a monophyletic clade due to the conserved mitochondrial gene rearrangement. This study provides useful information that aids in a better understanding of mitogenomic diversity and evolutionary patterns of Odontobutidae species.  相似文献   

7.
The mitochondrial genome (mitogenome) provides important information for phylogenetic analysis and understanding evolutionary origins. Herein, we sequenced, annotated, and characterised the mitogenome of the crab Helice wuana to better understand its molecular evolution and phylogeny. The 16,359 bp mitogenome includes 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, two ribosomal RNA (rRNA) genes and one control region. The genome composition is highly A + T biased 68.42%, and exhibits a negative AT–skew (? 0.036) and GC–skew (? 0.269) among Brachyura crabs. Gene rearrangements were detected, as was tandem duplication followed by random loss, which explains the translocation of mitochondrial genes. Phylogenetic analysis showed that H. wuana and H. tientsinensis clustered on one branch with high nodal support values. These results confirm that the placement of H. wuana within the Varunidae family of Thoracotrematan crabs. This study will provided a better understanding for gene rearrangements and crab evolution in the further.  相似文献   

8.
We successfully enriched a novel anaerobic ammonium-oxidizing (anammox) bacterium affiliated with the genus ‘Candidatus Brocadia’ with high purity (>90%) in a membrane bioreactor (MBR). The enriched bacterium was distantly related to the hitherto characterized ‘Ca. Brocadia fulgida’ and ‘Ca. Brocadia sinica’ with 96% and 93% of 16S ribosomal RNA gene sequence identity, respectively. The bacterium exhibited the common structural features of anammox bacteria and produced hydrazine in the presence of hydroxylamine under anoxic conditions. The temperature range of anammox activity was 20–45 °C with a maximum activity at 37 °C. The maximum specific growth rate (μmax) was 0.0082 h?1 at 37 °C, corresponding to a doubling time of 3.5 days. The half-saturation constant (KS) for nitrite was 5 ± 2.5 μM. The anammox activity was inhibited by nitrite (IC50 = 11.6 mM) but not by formate and acetate. The major respiratory quinone was identified to be menaquinone-7 (MK-7). The enriched anammox bacterium shared nearly half of genes with ‘Ca. Brocadia sinica’ and ‘Ca. Brocadia fulgida’. The enriched bacterium showed all known physiological characteristics of anammox bacteria and can be distinguished from the close relatives by its 16S rRNA gene sequence. Therefore, we proposed the name ‘Ca. Brocadia sapporoensis’ sp. nov.  相似文献   

9.
Eight mesorhizobial symbiotic strains isolated from Anthyllis vulneraria root-nodules were studied and compared taxonomically with defined Mesorhizobium species. All strains presented identical 16S rDNA sequences but can be differentiated by multilocus sequence analysis of housekeeping genes (recA, atpD, glnII and dnaK). Matrix-assisted laser desorption ionization-time-of-flight mass spectrometry analyses separate these strains in two groups and a separate strain. Levels of DNA–DNA relatedness were less than 55% between representative strains and their closest Mesorhizobium reference relatives. The two groups containing four and three strains, respectively, originating from border mine and non-mining areas in Cévennes, were further phenotypically characterized. Groupings were further supported by average nucleotide identity values based on genome sequencing, which ranged from 80 to 92% with their close relatives and with each other, confirming these groups represent new Mesorhizobium species. Therefore, two novel species Mesorhizobium delmotii sp. nov. (type strain STM4623T = LMG 29640T = CFBP 8436T) and Mesorhizobium prunaredense sp. nov. (type strain STM4891T = LMG 29641T = CFBP 8437T) are proposed. Type strains of the two proposed species share accessory common nodulation genes within the new symbiovar anthyllidis as found in the Mesorhizobium metallidurans type strain.  相似文献   

10.
Two strains (pedersoliT and girotti) of a new species of bacteria were isolated from the preen glands of wild Egyptian geese (Alopochen aegyptiacus) from the river Neckar in southern Germany in two subsequent years. The strains were lipophilic, fastidious, Gram-positive rods and belonged to the genus Corynebacterium. Phylogenetically, the isolates were most closely related to Corynebacterium falsenii DSM 44353T which has been found to be associated with birds before. 16S rRNA gene sequence similarity to all known Corynebacterium spp. was significantly <97%. Corresponding values of rpoB showed low levels of similarity <87% and ANIb was <73%. G + C content of the genomic DNA was 65.0 mol% for the type strain of the goose isolates, as opposed to 63.2 mol% in Corynebacterium falsenii. MALDI-TOF MS analysis of the whole-cell proteins revealed patterns clearly different from the related species, as did biochemical tests, and polar lipid profiles. We therefore conclude that the avian isolates constitute strains of a new species, for which the name Corynebacterium heidelbergense sp. nov. is proposed. The type strain is pedersoliT (=DSM 104638T = LMG 30044T).  相似文献   

11.
In the Porcelana Hot Spring (Northern Patagonia), true-branching cyanobacteria are the dominant primary producers in microbial mats, and they are mainly responsible for carbon and nitrogen fixation. However, little is known about their metabolic and genomic adaptations at high temperatures. Therefore, in this study, a total of 81 Fischerella thermalis strains (also known as Mastigocladus laminosus) were isolated from mat samples in a thermal gradient between 61–46 °C. The complementary use of proteomic comparisons from these strains, and comparative genomics of F. thermalis pangenomes, suggested that at least two different ecotypes were present within these populations. MALDI-TOF MS analysis separated the strains into three clusters; two with strains obtained from mats within the upper temperature range (61 and 54 °C), and a third obtained from mats within the lower temperature range (51 and 46 °C). Both groups possessed different but synonymous nifH alleles. The main proteomic differences were associated with the abundance of photosynthesis-related proteins. Three F. thermalis metagenome assembled genomes (MAGs) were described from 66, 58 and 48 °C metagenomes. These pangenomes indicated a divergence of orthologous genes and a high abundance of exclusive genes at 66 °C. These results improved the current understanding of thermal adaptation of F. thermalis and the evolution of these thermophilic cyanobacterial species.  相似文献   

12.
The complete mitochondrial genome plays an important role in the accurate inference of phylogenetic relationships among metazoans. Mactridae, also known as trough shells or duck clams, is an important family of marine bivalve clams in the order Veneroida. Here we present the complete mitochondrial genome sequence of the Xishishe Coelomactra antiquata (Mollusca: Bivalvia), which is the first representative from the family Mactridae. The mitochondrial genome of C. antiquata is of 17,384 bp in length, and encodes 35 genes, including 12 protein-coding, 21 transfer RNA, and 2 ribosomal RNA genes. Compared with the typical gene content of animal mitochondrial genomes, atp8 and tRNAS2 are missing. Gene order of the mitochondrial genome of C. antiquata is unique compared with others from Veneroida. In the mitochondrial genome of the C. antiquata, a total of 2189 bp of non-coding nucleotides are scattered among 26 non-coding regions. The largest non-coding region contains one section of tandem repeats (99 bp × 11), which is the second largest tandem repeats found in the mitochondrial genomes from Veneroida. The phylogenetic trees based on mitochondrial genomes support the monophyly of Veneridae and Lucinidae, and the relationship at the family level: ((Veneridae + Mactridae) + (Cardiidae + Solecurtidae)) + Lucinidae. The phylogenetic result is consistent with the morphological classification. Meanwhile, bootstrap values are very high (BP = 94–100), suggesting that the evolutionary relationship based on mitochondrial genomes is very reliable.  相似文献   

13.
Accurate data imputation requires ethnicity-matched reference panels. However, recent admixtures have created mosaic human genomes, different chromosomal segments have different ethnic backgrounds, so it is impossible for a single-ethnicity reference panel to be the matched for data imputation. In this study, we explored a novel strategy for imputation. We created individualized mosaic reference panel for each person according to his/her ethnic backgrounds at each genomic locus. We examined on datasets with 70% missing values on haplotypes and 50% missing values on genotypes. Results showed that the imputation with mosaic references steadily yielded high imputation accuracy and outperforms the other strategies. With the mosaic reference panels, the imputation accuracy was 98.8 ± 0.1% (CEU), 98.7 ± 0.1% (YRI), 98.5 ± 0.1% (CHB), 98.6 ± 0.1% (ASW), 97.3 ± 0.1% (MKK) and 98.2 ± 0.1% (MXL). Mosaic reference panel will be one option for future missing value imputation in big data era.  相似文献   

14.
The influence of temperature on the diurnal activity of five species of aphidophagous lady beetles (Coleoptera: Coccinellidae) was investigated between 0700 and 1900 h in chili (Capsicum annuum L.) agroecosystems and neighboring vegetation (goose grass, Eleusine indica L.). The lady beetle species observed were Menochilus sexmaculatus Fabricius, Coelophora inaequalis F., Coccinella transversalis F., Harmonia octomaculata F. and Coelophora bissellata Mulsant. More lady beetles (of all species) were found during cooler periods (at 0700, 0900, 1100, and 1900 h). The diurnal pattern of lady beetle adult was temperature dependent. On chili plants, numbers were higher at temperatures between 22 to 30 °C (at 0700, 0900, 1100 and 1900 h) and numbers decreased when temperatures were above 30 °C. When temperature was above 30 °C under the chili plant canopy, numbers were higher in neighboring goose grass, where temperatures were cooler (< 30 °C). Numbers of all species were negative correlated between chili plant and goose grass.  相似文献   

15.
Polygala tenuifolia Willd. is an important protected species used in traditional Chinese medicine. In the present study, amplified fragment length polymorphism (AFLP) markers were employed to characterize the genetic diversity in wild and cultivated P. tenuifolia populations. Twelve primer combinations of AFLP produced 310 unambiguous and repetitious bands. Among these bands, 261 (84.2%) were polymorphic. The genetic diversity was high at the species level: percentage of polymorphic loci (PPL) = 84.2%, Nei's gene diversity (h) = 0.3296 and Shannon's information index (I) = 0.4822. Between the two populations, the genetic differentiation of 0.1250 was low and the gene flow was relatively high, at 3.4989. The wild population (PPL = 81.9%, h = 0.3154, I = 0.4635) showed a higher genetic diversity level than the cultivated population (PPL = 63.9%, h = 0.2507, I = 0.3688). The results suggest that the major factors threatening the persistence of P. tenuifolia resources are ecological and human factors rather than genetic. These results will assist with the design of conservation and management programs, such as in natural habitat conservation, setting the excavation time interval for resource regeneration and the substitution of cultivated for wild plants.  相似文献   

16.
Strains T5K1 and AV446 isolated from apple cider vinegars during a submerged vinegar production in two separate vinegar facilities showed 94% 16S rRNA gene similarity to its closest neighbors Komagataeibacter maltaceti LMG 1529T and Gluconacetobacter entanii LTH 4560T. Further phylogenetic and phenotypic characterizations indicated that the isolates belonged to a novel species of the Komagataeibacter genus. Comparison based on 16S–23S rRNA gene ITS sequences and concatenated partial sequences of the housekeeping genes dnaK, groEL and rpoB, grouped both strains to a single phylogenetic cluster well separated from the other species of the Komagataeibacter genus. Average nucleotide identity of T5K1 and AV446 draft genome sequences compared to other Komagataeibacter type strains was below 94% and at the same time, in-silico DNA–DNA hybridization was below 70%. Both strains on the other hand showed approximately 98% (average nucleotide identity) and 87% (in silico DNA–DNA hybridization) similarity to each other. Strains T5K1 and AV446 can be differentiated from other Komagataeibacter type strains based on their ability to produce 2-keto-d-gluconic acid and at the same time inability to produce 5-keto-d-gluconic acid. Furthermore, strains of the new species do not grow on Asai medium supplemented with d-glucose or d-mannitol. The growth is also absent (T5K1) or weak (AV446) on Hoyer–Frateur medium supplemented with afore mentioned sugars. Both strains produce cellulose. In addition, draft genome analysis revealed that strains T5K1 and AV446 possess genes involved in the synthesis of acetan-like extracellular heteropolysaccharide. We propose the name Komagataeibacter pomaceti sp. nov. for the new species with LMG 30150T [= CCM 8723T = ZIM B1029T] as the type strain. Data collected in this study and in a previous study also revealed that Komagataeibacter kombuchae is a later heterotypic synonym of Komagataeibacter hansenii.  相似文献   

17.
In a screening by multilocus sequence analysis of Pseudomonas strains isolated from diverse origins, 4 phylogenetically closely related strains (FBF58, FBF102T, FBF103, and FBF122) formed a well-defined cluster in the Pseudomonas syringae phylogenetic group. The strains were isolated from citrus orchards in northern Iran with disease symptoms in the leaves and stems and its pathogenicity against citrus plants was demonstrated. The whole genome of the type strain of the proposed new species (FBF102T = CECT 9164T = CCUG 69273T) was sequenced and characterized. Comparative genomics with the 14 known Pseudomonas species type strains of the P. syringae phylogenetic group demonstrated that this strain belonged to a new genomic species, different from the species described thus far. Genome analysis detected genes predicted to be involved in pathogenesis, such as an atypical type 3 secretion system and two type 6 secretion systems, together with effectors and virulence factors. A polyphasic taxonomic characterization demonstrated that the 4 plant pathogenic strains represented a new species, for which the name Pseudomonas caspiana sp. nov. is proposed.  相似文献   

18.
The importance of birds in the biological cycle of Neospora caninum is not clear. We report unsuccessful Neospora infection in chickens (Gallus gallus domesticus) using two isolates of N. caninum. In experiment #1, 30 White Leghorn chickens were orally inoculated with viable N. caninum oocysts (NC-SP1 isolate, 200 oocysts per bird) via the crop at 21 days of age. Groups of three birds were euthanised at intervals of 7 days (a total of 9 weeks) and one group was challenged with the same oocyst dose at 37 days p.i. and observed for 11 weeks. Blood samples were collected weekly, and sera were tested using IFAT. Chicken tissues were collected for PCR, quantitative PCR and immunohistochemistry. Two dogs approximately 45 days of age were fed with tissues from chickens euthanised at 138 and 159 days p.i. The results indicated that the chickens were resistant to neosporosis as revealed by failure to seroconvert, to detect parasite DNA or N. caninum antigen by immunohistochemistry in inoculated bird tissues, and by no oocyst excretion by the dogs fed avian tissues. Similar results were obtained in experiment #2, in which 34 1-week-old chickens were each s.c. inoculated with 100,000 tachyzoites of the NcWTDMn1 isolate of N. caninum. The chickens were euthanised on days 7, 15, 22, 28, 36 and 60 p.i. At necropsy, all tissues and serum from each bird were collected. All chickens remained asymptomatic, and N. caninum antigen was not detected by immunohistochemistry. Seven chickens euthanised at day 60 p.i. demonstrated low (1:25 dilution) levels of antibodies by using the Neospora agglutination test. Two 12-week-old dogs fed tissues pooled from 10 inoculated chickens euthanised at day 60 p.i. did not excrete N. caninum oocysts. This investigation indicates that chickens are resistant to experimental infection by N. caninum.  相似文献   

19.
20.
Afrotropical ant-following birds are vulnerable to forest loss and disturbance, but critical habitat thresholds regarding their abundance and species richness in human-dominated landscapes, including industrial oil palm plantations, have never been assessed. We measured forest cover through Landsat imagery and recorded species richness and relative abundance of 20 ant-following birds in 48 plots of 1-km2, covering three landscapes of Southwest Cameroon: Korup National Park, smallholder agroforestry areas (with farms embedded in forest), and an industrial oil palm plantation. We evaluated differences in encounter frequency and species richness among landscapes, and the presence of critical thresholds through enhanced adaptive regression through hinges. All species were detected in Korup National Park and the agroforestry landscape, which had similar forest cover (>85%). Only nine species were found in the oil palm plantation (forest cover = 10.3 ± 3.3%). At the 1-km2 scale, the number of species and bird encounters were comparable in agroforests and the protected area: mean species richness ranged from 12.2 ± 0.6 in the park and 12.2 ± 0.6 in the agroforestry matrix to 1.0 ± 0.4 in the industrial oil palm plantation; whereas encounters decreased from 34.4 ± 3.2 to 26.1 ± 2.9 and 1.3 ± 0.4, respectively. Bird encounters decreased linearly with decreasing forest cover, down to an extinction threshold identified at 24% forest cover. Species richness declined linearly by ca. one species per 7.4% forest cover lost. We identified an extinction threshold at 52% forest cover for the most sensitive species (Criniger chloronotus, Dicrurus atripennis, and Neocossyphus poensis). Our results show that substantial proportions of forests are required to sustain complete ant-following bird assemblages in Afrotropical landscapes and confirm the high sensitivity of this bird guild to deforestation after industrial oil palm development. Securing both forest biodiversity and food production in an Afrotropical production landscape may be best attained through a combination of protected areas and wildlife-friendly agroforestry.  相似文献   

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