Morphological and phylogenetic analyses reveal a new species of Anthracophyllum (Omphalotaceae, Agaricales) in Zhejiang Province, China.

During the investigations of macrofungi resources in Zhejiang Province, China, an interesting wood rot fungus was collected. Based on morphological and molecular phylogenetic studies, it is described as a new species, Anthracophyllum sinense. A. sinense is characterized by its sessile, charcoal black and pleurotoid pileus, sparse lamellae occasionally branching, clavate basidia with long sterigmata [(3-)6-7(-8) µm], and non-heteromorphous cystidia. A. sinense establishes a separate lineage close to A. archeri and A. lateritium in the phylogenetic tree.

Retiboletus atrofuscus (Boletaceae, Boletales), a new species from China.

Based on morphological and phylogenetic analyses, an ectomycorrhizal fungus collected from Jiangxi, China, is described as a new species. R. atrofuscus is morphological characterized by a dark gray to black pileus, white to pale yellowish white hymenophore, a grayish brown to pale yellow context, which turning orange-yellow to rusty yellow when injured, a prominently and coarsely white to pale yellow to black reticulation on upper 3/4 or entire stipe, grayish yellow to pale yellow to yellowish brown basidiospores in KOH with measuring (7-)7.5-13(-13.5) × (3-)3.5-5(-5.5) µm. Phylogenetic analysis results showed that R. atrofuscus formed an independent lineage within Retiboletus. Descriptions and hand drawings of the new species and comparisons with similar species are presented.

Morphophysiological responses of detached and adhered biofilms of Pseudomonas fluorescens to acidic electrolyzed water.

Pseudomonas spp. have emerged as the main spoilage bacteria, with many strains easily forming biofilms on food-contact surfaces and causing cross-contamination. The efficacy of disinfectants against bacteria is usually tested with planktonic cells; however, the disinfection tolerance of biofilms, especially detached biofilms, remains unknown. Here, we investigated the tolerance responses of detached and adhered biofilms of Pseudomonas fluorescens to acidic electrolyzed water (AEW) by determining tolerance responses by plate counting, comparing them using a Weibull model, and verifying changes in bacterial morphology by scanning electron microscopy. The experimental data and the responses calculated using Weibull a (scale) and b (shape) parameters agreed well (R2 values: 0.974-0.999), and we found that AEW exhibited effective antimicrobial activity against P. fluorescens, with adhered biofilms were more resistant than detached biofilms and planktonic cells. Additionally, AEW increased the bacterial membrane permeability and decreased the membrane potential, intracellular ATP concentrations, and intracellular pH while also triggering the disruption of extracellular polymeric substances. These results demonstrated that the morphophysiological responses of detached and adhered biofilms differed significantly and provided information on disinfectant-resistance strategies potentially beneficial to the development of novel disinfection approaches.

Effects of the Endophytic Bacteria Bacillus cereus BCM2 on Tomato Root Exudates and Meloidogyne incognita Infection.

Root-knot nematodes (Meloidogyne spp.) cause serious crop losses worldwide. The colonization of tomato roots by endophytic bacteria Bacillus cereus BCM2 can greatly reduce Meloidogyne incognita damage, and tomato roots carrying BCM2 were repellent to M. incognita second-stage juveniles (J2). Here, the effects of BCM2 colonization on the composition of tomato root exudates was evaluated and potential mechanisms for BCM2-mediated M. incognita control explored using a linked twin-pot assay and GC-MS. On water agar plates, J2 preferentially avoided filter paper treated with tomato root exudates (organic phase only) from plants inoculated with BCM2, visiting these 67.1% less than controls. In a linked twin-pot assay, BCM2 treatment resulted in a 42.0% reduction in the number of nematodes in the soil, a 43.3% reduction in the number of galls and a 47.7% decrease in the density of M. incognita in root tissues. Analysis of root exudate composition revealed that BCM2 inoculation increased the number of components in exudates. Among these, 2,4-di-tert-butylphenol, 3,3-dimethyloctane, and n-tridecane secretions markedly increased. In repellency trials on water agar plates, J2 avoided 2,4-di-tert-butylphenol, n-tridecane, and 3,3-dimethyloctane at concentrations of 4 mmol/liter. In a linked twin-pot assay, inoculation with 2,4-di-tert-butylphenol or 3,3-dimethyloctane reduced the number of nematodes in the soil (by 54.9 and 70.6%, respectively), the number of galls (by 53.7 and 52.4%), and the number of M. incognita in root tissues (by 67.5 and 36.3%). BCM2 colonization in tomato roots affected the composition of root exudates, increasing the secretion of substances that appear to be repellent, thus decreasing M. incognita J2 infection of roots.

Endophytic Bacillus cereus Effectively Controls Meloidogyne incognita on Tomato Plants Through Rapid Rhizosphere Occupation and Repellent Action.

Root-knot nematodes (Meloidogyne spp.), which cause severe global agricultural losses, can establish a special niche in the root vascular cylinder of crops, making them difficult to control. Endophytic bacteria have great potential as biocontrol organisms against Meloidogyne incognita. Three endophytic bacteria were isolated from plant tissues and showed high nematicidal activity against M. incognita second-stage juveniles (J2) in vitro. The gyrB gene sequence amplification results indicated that the three isolates were Bacillus cereus BCM2, B. cereus SZ5, and B. altitudinis CCM7. The isolates colonized tomato roots rapidly and stably during the colonization dynamic experiment. Three pot experiments were designed to determine the potential of three endophytic bacterial isolates on control of root-knot nematodes. The results showed that the preinoculated B. cereus BCM2 experiment significantly reduced gall and egg mass indexes. The inhibition ratio of gall and egg mass was up to 81.2 and 75.6% on tomato roots and significantly enhanced shoot length and fresh weight. The other two experiments with inoculated endophytic bacteria and M. incognita at the same time or after morbidity had lower inhibition ratios compared with the preinoculated endophytic bacteria experiment. The confocal laser-scanning microscopy method was used to further study the possible mechanism of endophytic bacteria in the biocontrol process. The results showed the localization pattern of the endophytic bacteria B. cereus BCM2-(str')-pBCgfp-1 in tomato root tissues. Root tissue colonized by endophytic bacteria repelled M. incognita J2 infection compared with the untreated control in a repellence experiment. We isolated an endophytic B. cereus strain that stably colonized tomato and controlled M. incognita effectively. This strain has potential for plant growth promotion, successful ecological niche occupation, and M. incognita J2 repellent action induction. It plays an important role in endophytic bacteria against root-knot nematodes.

Four novel species of Pleurotheciaceae collected from freshwater habitats in Jiangxi Province, China.

During an investigation of fungal diversity from freshwater environments in different regions in Jiangxi Province, China, four interesting species were collected. Morphology coupled with combined gene analysis of an ITS, LSU, SSU, and rpb2 DNA sequence data showed that they belong to the family Pleurotheciaceae. Four new species, Pleurotheciella ganzhouensis, Pla. irregularis, Pla. verrucosa, and Pleurothecium jiangxiense are herein described. Pleurotheciella ganzhouensis is characterized by its capsule-shaped conidia and short conidiophores, while Pla. irregularis has amorphous conidiophores and 3-septate conidia. Pleurotheciella verrucosa has cylindrical or verrucolose conidiogenous cells, 1-septate, narrowly fusiform, meniscus or subclavate conidia. Pleurothecium jiangxiense characterized in having conidiogenous cells with dense cylindrical denticles and short conidiophores. Pleurothecium obovoideum was transferred to Neomonodictys based on phylogenetic evidence. All species are compared with other similar species and comprehensive descriptions, micrographs, and phylogenetic data are provided.

Multi-gene phylogenetic analyses revealed two novel species and one new record of Trichobotrys (Pleosporales, Dictyosporiaceae) from China.

The rotting wood in freshwater is a unique eco-environment favoring various fungi. During our investigation of freshwater fungi on decaying wood, three hyphomycetes were collected from Jiangxi and Guangxi Provinces, China. Based on the morphological observations and phylogenetic analysis of a combined DNA data containing ITS, LSU, SSU and tef1-α sequences, two new Trichobotrys species, T.meilingensis and T.yunjushanensis, as well as a new record of T.effusa, were introduced. Additionally, a comprehensive description of the genus with both morphological and molecular data was first provided.

A Small RNA, SaaS, Promotes Salmonella Pathogenicity by Regulating Invasion, Intracellular Growth, and Virulence Factors.

Salmonella enterica serovar Enteritidis is a common foodborne pathogen that infects both humans and animals. The S. Enteritidis virulence regulation network remains largely incomplete, and knowledge regarding the specific virulence phenotype of small RNAs (sRNAs) is limited. Here, we investigated the role of a previously identified sRNA, Salmonella adhesive-associated sRNA (SaaS), in the virulence phenotype of S. Enteritidis by constructing mutant (ΔsaaS) and complemented (ΔsaaS/psaaS) strains. SaaS did not affect S. Enteritidis; it was activated in the simulated intestinal environment (SIE), regulating the expression of virulence target genes. We discovered that it directly binds ssaV mRNA. Caco-2 and RAW 264.7 cell assays revealed that SaaS promoted S. Enteritidis invasion and damage to epithelial cells while suppressing macrophage overgrowth and destruction. Furthermore, a BALB/c mouse model demonstrated that the deletion of SaaS significantly reduced mortality and attenuated the deterioration of pathophysiology, bacterial dissemination into systemic circulation, and systemic inflammation. Our findings indicate that SaaS is required for S. Enteritidis virulence and further highlight its biological role in bacterial pathogenesis. IMPORTANCE Salmonella is a zoonotic pathogen with high virulence worldwide, and sRNAs have recently been discovered to play important roles. We explored the biological characteristics of the sRNA SaaS and developed two cell infection models and a mouse infection model. SaaS is an SIE-responsive sRNA that regulates the expression of virulence-targeted genes. Additionally, it differentially mediates invasion and intracellular growth for survival and infection of the epithelium and macrophages. We further found that SaaS enhanced bacterial virulence by promoting lethality, colonization, and inflammatory response. These findings provide a better understanding of the critical role of sRNA in bacterial virulence.

Phylogenetic and Morphological Evidence Reveal Five New Species of Boletes from Southern China.

Fungi of the order Boletales are extremely important in both ecology and economy, since most of them are ectomycorrhizal fungi, which play vital roles in maintaining forest ecosystems, water and soil protection, vegetation restoration and so on. Although previous studies have shown that this order has a very high species diversity in China, there are few reports on the species diversity of boletes in Jiangxi Province, China. Based on morphological (macroscopic and microscopic morphological characteristics) and phylogenetic analyses (ITS, LSU, and TEF1-α sequences), in this study, the wild boletes in Jiangxi Province were investigated, and five new species are described: Austroboletus albus, Xanthoconium violaceipes, Xanthoconium violaceofuscum, Xerocomus rutilans and Xerocomus subsplendidus. Descriptions and hand drawings of the new species are presented.

A new species of Dictyochaeta (Sordariomycetes, Chaetosphaeriales, Chaetosphaeriaceae) from freshwater habitats in China.

Background: Freshwater fungi refer to the fungi that depend on the freshwater habitats for the whole life cycle or part of their life cycle. In this context, a new aquatic hyphomycete was isolated from decaying wood in a freshwater habitat in Jiangxi Province, China. New information: Dictyochaetajiangxiensis sp. nov., a new aquatic hyphomycete, is characterised by its unbranched, septate, base-fertile conidiophores with multisepta and single phialide at the apex, brown, sterile seta, monophialidic, subcylindrical conidiogenous cells narrowing below the funnel-shaped collarette, hyaline, unicellular, thin-walled, smooth, guttulate, falcate to subclavate conidia narrowly rounded at both ends with hair-like appendages. Phylogenetically, the new species Dictyochaetajiangxiensis clustered together with Dictyochaetabrevis MFLU 19-0216 in a well-supported clade, but formed a separate branch. In order to better define the taxonomic status of the new species, a phylogenetic tree of most closely-related taxa in Chaetosphaeriaceae was established, based on multi-locus sequences (ITS and LSU). The novel species is described and illustrated. Newly-generated molecular data of Dictyochaetajiangxiensis is also provided.

Preliminary Studies on the Effects of Oyster Mushroom Spherical Virus China Strain on the Mycelial Growth and Fruiting Body Yield of the Edible Mushroom Pleurotus ostreatus.

Oyster mushroom spherical virus (OMSV) is a positive-sense single-stranded RNA mycovirus which is associated with a devastating oyster mushroom die-back disease. However, little is known about its diversity, and the effects of OMSV infection on its fungal host are not well understood. In this study, we determined the nearly complete nucleotide sequence of OMSV isolated from cultivated oyster mushrooms in China. Sequence analysis suggested that the virus represents a new strain of OMSV (referred to here as OMSV-Ch). A GenBank BLAST search of the genomic sequences demonstrated that the OMSV-Ch had the highest identity (74.9%) with the OMSV from Korea (OMSV-Kr). At the amino acid-sequence level, these two strains shared 84.1% identity in putative replication protein (RP) and 94.1% identity in coat protein (CP). Phylogenetic analysis based on RP showed that OMSV-Ch clustered with OMSV-Kr, closely related to Tymoviridae. Phylogenetic analysis based on both the RP and CP showed that OMSV had a distant clade relationship with tymoviruses, marafiviruses, and maculaviruses. We obtained the OMSV-Ch-free Pleurotus ostreatus strain via single hyphal tip cultures combined with high-temperature treatment. Preliminary studies indicate that OMSV-Ch can significantly inhibit mycelial growth, cause malformations of the fruiting bodies, and reduce the yield of P. ostreatus. Co-cultivation resulted in horizontal transmission of the OMSV-Ch to a virus-cured strain. The findings of our study contribute to the prevention and control of mycoviral diseases in the future.

Three novel species of Distoseptispora (Distoseptisporaceae) isolated from bamboo in Jiangxi Province, China.

Decaying bamboo in freshwater is a unique eco-environment for fungi. Three new Distoseptispora (Distoseptisporaceae) species, D.meilingensis, D.yongxiuensis and D.yunjushanensis from submerged decaying bamboo culms in Jiangxi Province, China, were discovered, based on phylogenetic analyses and morphological characters. The combined data of ITS-LSU-SSU-Tef1 sequences were used to infer the phylogenetic relationship between D.meilingensis, D.yongxiuensis, D.yunjushanensis and related species. Both molecular analyses and morphological data supported D.meilingensis, D.yongxiuensis and D.yunjushanensis as three independent taxa.

Phaeoisarialaianensis (Pleurotheciales, Pleurotheciaceae), a new species from freshwater habitats in China.

Background: Freshwater fungi play an indispensable role in the ecosystem and have great research value. Based on morphological and phylogenetic analyses of a concatenated dataset of ITS, LSU and SSU sequences, a new species, Phaeoisarialaianensis, was introduced as a freshwater hyphomycete from Anhui Province, China. New information: Phaeoisarialaianensis was morphologically described as erect, rigid, dark brown to black, velvety synnemata which has macronematous, septate, branched, brown to dark brown, parallel adpressed conidiophores with polyblastic, integrated, terminal, hyaline to pale brown, smooth, denticulate, sympodial conidiogenous cells and ellipsoidal to obovoid, rounded at the apex, obtuse and tapering towards base, septate, guttulate conidia. Based on molecular and morphological characteristics, it is confirmed to be a new species. All illustrations and descriptions have been provided.

Sporidesmiellalignicola sp. nov., a new hyphomycetous fungus from freshwater habitats in China.

BACKGROUND: Freshwater fungi, growing on submerged wood, can promote the degradation of organisms and the reuse of rotten wood energy and play key roles in freshwater ecosystems. Here, a new hyphomycetous fungus, Sporidesmiellalignicola, was isolated and identified from submerged wood samples collected in a small stream in Jiangxi Province, south-eastern China. NEW INFORMATION: The new taxon was studied, based on morphological characters and phylogenetic analyses combined with LSU, ITS, TEF1α and RPB2 sequences data. Sporidesmiellalignicola was morphologically characterised by its pink colonies on PDA medium in prophase, macronematous, mononematous, solitary, brown, septate, unbranched, straight or slightly flexuous conidiophores with holoblastic, polyblastic, integrated, terminal, pale brown conidiogenous cells and cylindrical, narrowly clavate, broadly obovoid to cuneiform, 3-4-distoseptate, olivaceous brown or brown conidia with rounded apex. A phylogenetic tree was constructed, based on the combination of LSU, ITS, TEF1α and RPB2 sequences data.

Tumor feeding artery reconstruction with multislice spiral CT in the diagnosis of pelvic tumors of unknown origin.

PURPOSE: We aimed to compare multislice spiral computed tomography (MSCT) angiography diagnosis with both surgical findings and postoperative pathological results in patients with pelvic tumors of unknown origin. In addition, the diagnostic accuracy of MSCT angiography was compared with that of routine computed tomography for tumor feeding artery volume reconstruction to determine the origin and nature of pelvic tumors. MATERIALS AND METHODS: The records of 43 patients with pelvic tumors of unknown origin who underwent MSCT angiography were retrospectively reviewed. Volume reconstructions using add vessel and merge views methods were performed for abdominal and pelvic blood vessels. The tumor origin was identified based on observations of the origin, number, morphology, starting/ending locations, route, and distribution of the tumor feeding arteries. RESULTS: Overall, the mean tumor diameter was 9.8±3.5 cm (range, 4.2-23.5 cm); 11 tumors (25.6%) were cystic in nature; and 32 tumors (74.4%) were either solid/cystic or solid in nature. When considering all MSCT angiography examinations used to predict the nature of the tumor (e.g., malignant or benign), the sensitivity and specificity were 77.3% and 95.2%, respectively. The positive and negative predictive values were 94.4% and 80%, respectively. The overall diagnostic accuracy was 86.05% with an area under the curve of 0.961 (95% confidence interval, 0.913-1.000). CONCLUSIONS: MSCT angiography volume reconstruction for pelvic tumor feeding arteries of unknown origin is highly valuable for localization, qualitative diagnosis, and quantitative diagnosis of pelvic tumors.