Genetic diversities in wild and cultivated populations of the two closely-related medical plants species, Tripterygium Wilfordii and T. Hypoglaucum (Celastraceae).

BACKGROUND: The sustainable supply of medicinal plants is important, and cultivating and domesticating them has been suggested as an optimal strategy. However, this can lead to a loss of genetic diversity. Tripterygium wilfordii Hook. f. is a medicinal plant commonly used in traditional Chinese medicine, but its wild populations are dwindling due to excessive harvesting. To protect the species and meet the increasing demand, it is urgent to cultivate it on a large scale. However, distinguishing between T. wilfordii and T. hypoglaucum, two similar species with different medicinal properties, is challenging. Therefore, it is crucial to understand the genetic diversity and population structure of these species for their sustainable utilization. RESULTS: In this study, we investigated the genetic diversity and population structure of the two traditional medicinal semiwoody vines plant species, Tripterygium wilfordii and T. hypoglaucum, including wild and cultivated populations using chloroplast DNA (cpDNA) sequences and microsatellite loci. Our results indicated that the two species maintain a high level of genetic divergence, indicating possible genetic bases for the different contents of bioactive compounds of the two species. T. wilfordii showed lower genetic diversity and less subdivided population structures of both markers than T. hypoglaucum. The potential factors in shaping these interesting differences might be differentiated pollen-to-seed migration rates, interbreeding, and history of population divergence. Analyses of cpDNA and microsatellite loci supported that the two species are genetically distinct entities. In addition, a significant reduction of genetic diversity was observed for cultivated populations of the two species, which mainly resulted from the small initial population size and propagated vegetative practice during their cultivation. CONCLUSION: Our findings indicate significant genetic divergence between T. wilfordii and T. hypoglaucum. The genetic diversity and population structure analyses provide important insights into the sustainable cultivation and utilization of these medicinal plants. Accurate identification and conservation efforts are necessary for both species to ensure the safety and effectiveness of crude drug use. Our study also highlighted the importance of combined analyses of different DNA markers in addressing population genetics of medicinal plants because of the contrasts of inheritance and rates of gene flow. Large-scale cultivation programs should consider preserving genetic diversity to enhance the long-term sustainability of T. wilfordii and T. hypoglaucum. Our study proposed that some populations showed higher genetic diversity and distinctness, which can be considered with priority for conservation and as the sources for future breeding and genetic improvement.

The Expression of Parthanatos Markers and miR-7 Mimic Protects Photoreceptors from Parthanatos by Repressing α-Synuclein in Retinal Detachment.

Retinal detachment (RD) refers to the separation between the neuroepithelium and the pigment epithelium layer. It is an important disease leading to irreversible vision damage worldwide, in which photoreceptor cell death plays a major role. α-Synuclein (α-syn) is reportedly involved in numerous mechanisms of neurodegenerative diseases, but the association with photoreceptor damage in RD has not been studied. In this study, elevated transcription levels of α-syn and parthanatos proteins were observed in the vitreous of patients with RD. The expression of α-syn- and parthanatos-related proteins was increased in experimental rat RD, and was involved in the mechanism of photoreceptor damage, which was related to the decreased expression of miR-7a-5p (miR-7). Interestingly, subretinal injection of miR-7 mimic in rats with RD inhibited the expression of retinal α-syn and down-regulated the parthanatos pathway, thereby protecting retinal structure and function. In addition, interference with α-syn in 661W cells decreased the expression of parthanatos death pathway in oxygen and glucose deprivation model. In conclusion, this study demonstrates the presence of parthanatos-related proteins in patients with RD and the role of the miR-7/α-syn/parthanatos pathway in photoreceptor damage in RD.

Luteipulveratus flavus sp. nov. isolated from two lichen species.

Two novel strains, YIM 133132T and YIM 133296, were isolated from lichen samples collected from Yunnan Province, Southwest PR China. YIM 133132T and YIM 133296 are aerobic, Gram-staining-positive, non-motile actinomycetes. They are also catalase-positive and oxidase-negative, and YIM 133132T formed flat yellowish colonies that were relatively dry on YIM38 agar medium. Flat yellowish colonies of YIM 133296 were also observed on YIM38 agar medium. YIM 133132T grew at 25-35 °C (optimum 25-30 °C), pH 6.0-9.0 (optimum pH 7.0) and in the presence of 0-8% (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strains YIM 133132T and YIM 133296 represented members of the genus Luteipulveratus and exhibited high sequence similarity (96.93%) with Luteipulveratus halotolerans C296001T. The genomic DNA G+C content of both strains was 71.8%. The DNA-DNA hybridisation (dDDH) values between YIM 133132T and YIM 133296 were 85.1%, and the DNA-DNA hybridisation value between YIM 133132T and YIM 133296 and L. halotolerans C296001T was 23.4%. On the basis of the draft genome sequences, the average nucleotide identity (ANI) between strains YIM 133132T and YIM 133296 and L. halotolerans C296001T was 80.8%. The major menaquinones that were identified were MK-8(H4), MK-9 and MK-8(H2). The polar lipids were diphosphatidylglycerol and phosphatidylinositol. On the basis of the morphological, physiological, biochemical, genomic, phylogenetic and chemotaxonomic characteristics, strains YIM 133132T and YIM 133296 can be clearly distinguished from L. halotolerans C296001T, and the two strains represent a novel species for which the name L. flavus sp. nov. is proposed. The type strain is YIM 133132T (CGMCC= 1.61357T and KCTC= 49824T).

Exosomes derived from thymic stromal lymphopoietin-treated dendritic cells regulate T helper 17/regulatory T cell differentiation via miR-21/Smad7 axis.

Thymic stromal lymphopoietin (TSLP) is associated with fungal keratitis. This work aims to investigate whether TSLP can regulate T helper (Th) 17 and regulatory T cell (Treg) differentiation. We separated dendritic cells (DCs) from peripheral blood of healthy volunteers. DCs were treated with TSLP to activate DCs, and exosomes were obtained. CD+ T cells were incubated with exosomes from TSLP-treated DCs. We found that exosomes from TSLP-treated DCs notably promoted the proportions of Th17 cells and inhibited the proportions of Tregs in the CD4+ T cells. Moreover, exosomes from TSLP-treated DCs enhanced the expression of retinoid-related orphan receptor γt (RORγt) and interleukin 17 (IL-17), and repressed the expression of forkhead box protein P3 (Foxp3) and interleukin 10 (IL-10) in the CD4+ T cells. Furthermore, miR-21 was highly expressed in exosomes from TSLP-treated DCs. Exosomes from TSLP-treated miR-21-silenced DCs promoted Treg differentiation and suppressed Th17 differentiation. Smad7 up-regulation repressed Th17 differentiation and enhanced Treg differentiation, which was abolished by miR-21 overexpression. Smad7 overexpression rescued the effect of exosomes from TSLP-treated DCs on Th17/Treg differentiation. In conclusion, our article confirms that TSLP induces DCs to deliver miR-21 by secreting exosomes, and thus miR-21 regulates Th17/Treg differentiation by inhibiting Smad7. Thus, this work further reveals the biological role of miR-21 in fungal keratitis.

EphA2 inhibits SRA01/04 cells apoptosis by suppressing autophagy via activating PI3K/Akt/mTOR pathway.

This study attempted to determine the effect of EphA2 on H2O2-treated lens epithelial cells (SRA01/04) and the underlying mechanisms. MTT assay and flow cytometry were performed to assess cell viability and cell apoptosis. Western blot was carried out to examine the levels of proteins associated with apoptosis and autophagy. Our results revealed that EphA2 significantly elevated the reduced cell viability, and inhibited the increased cell apoptosis in H2O2-treated SRA01/04 cells, along with the significant up-regulated Bcl-2 and down-regulated Cleaved-caspase-3 and Bax protein levels, but which were all abolished by Rapa (autophagy activator). We also found that EphA2 significantly suppressed cell autophagy in H2O2-treated SRA01/04 cells. Additionally, EphA2 significantly up-regulated the protein levels of p-Akt and p-mTOR in H2O2-treated SRA01/04 cells, and the inhibition of Akt by MK-2206 and inhibition of mTOR by Rapa both obviously reversed EphA2-mediated the inhibition of autophagy in H2O2-treated SRA01/04 cells. In summary, these data demonstrated that EphA2 inhibited the apoptosis of SRA01/04 cells by inhibiting autophagy via activating PI3K/Akt/mTOR pathway.

Glaciibacter flavus sp. nov., isolated from a lichen sample.

A novel Actinobacterium strain YIM 131861 T, was isolated from lichen collected from the South Bank Forest of the Baltic Sea, Germany. It was Gram-stain-positive, strictly aerobic, catalase positive and oxidase negative, yellow pigmented. Cells were motile with a polar flagellum, irregular rod shaped and did not display spore formation. The strain grew at 15 - 30 °C (optimum 25 °C), at pH 6.0 - 10.0 (optimum pH 7.0) and in the presence of 0 - 1.5% (w/v) NaCl (optimum 1%). Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain YIM 131861 T belonged to the genus Glaciibacter, and exhibited a high sequence similarity (96.4%) with Glaciibacter superstes NBRC 104264 T. The genomic DNA G + C content of strain YIM 131861 T was 68.2 mol%. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain YIM 131861 T and Glaciibacter superstes NBRC 104264 T were 73.2 and 19.9% based on the draft genome sequence. The cell-wall peptidoglycan type was B2γ and contained the 2, 4-diaminobutyric acid as the diagnostic amino acid. Whole cell sugars were galactose, rhamnose, ribose and glucose. It contained MK-12 and MK-13 as the predominant menaquinones. The major cellular fatty acids (> 10%) were identified as anteiso-C15:0, iso-C16:0 and anteiso-C17:0. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol and two unknown glycolipids. Based on the results of phenotypic, chemotaxonomic and phylogenetic analyses, strain YIM 131861 T should belong to the genus Glaciibacter and represents a novel species of the genus Glaciibacter, for which the name Glaciibacter flavus sp. nov. is proposed. The type strain is YIM 131861 T (= CGMCC 1.16588 T = NBRC 113572 T).

Nakamurella leprariae sp. nov., isolated from a lichen sample.

A novel actinobacterium, YIM 132084T, was isolated from Lepraria sp. lichen collected from Yunnan province, south-west PR China and identified by a polyphasic taxonomic approach. The strain was Gram-stain-positive, aerobic, catalase-positive, oxidase-negative, non-motile and coccus-shaped. Colonies were round, convex, smooth and light orange yellow in color. It grew at 10-40 °C (optimum 28 °C), at pH 6.0-11.0 (optimum pH 7.0) and in the presence of 0-4% NaCl (optimum 0%). Strain YIM 132084T comprised diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol as the major polar lipids, MK-8(H4) as the predominant menaquinone, and anteiso-C15:0, anteiso-C17:0, iso-C15:0 and iso-C16:0 as major fatty acids. Strain YIM 132084T had meso-diaminopimelic acid as the diagnostic diamino acid in the cell-wall peptidoglycan, and mannose, ribose, glucose and rhamnose as whole-cell sugars. The 16S rRNA gene sequence showed high level of similarity with Nakamurella flavida KCTC 19127T (97.7%) and Nakamurella flava CGMCC 4.7524T (97.7%). The G + C content of the genomic DNA was 72.4 mol%. Based on draft genome sequences, strain YIM 132084T showed an average nucleotide identity value of 76.1% and 74.9%, a digital DNA-DNA hybridization value of 20.9% and 20.6% with the reference strains Nakamurella flavida and Nakamurella flava, respectively. The results of the phenotypic, chemotaxonomic and phylogenetic analyses showed that strain YIM 132084T represents a novel species of the genus Nakamurella, for which the name Nakamurella leprariae sp. nov. is proposed. The type strain is YIM 132084T (= CGMCC 4.7667T = NBRC 114280T = KCTC 49367T).

Paracoccus lichenicola sp. nov., Isolated from Lichen.

Strain YIM 132242T, isolated from lichen collected from Pu'er, Yunnan Province, China, was short-rod-shaped, Gram-reaction-negative, aerobic, catalase- and oxidase-positive. Growth of the strain was occurred at 10-39 °C (optimum, 28-35 °C), at pH 4.0-10.0 (optimum, pH 7.0-8.0) and at salinities of 0-8% (w/v) NaCl (optimum, 0-2%). Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain YIM 132242T belonged to the genus Paracoccus and had the highest levels of sequence similarity to Paracoccus aerius KCTC 42845T (97.0% similarity), Paracoccus sediminis CMB17T (96.8% similarity), and Paracoccus fontiphilus MVW-1T (96.4% similarity). The major fatty acid was identified as C18:1 ω7c (77.6%). The predominant respiratory quinone was ubiquinone-10 (Q-10). Polar lipid analysis indicated the presence of phosphatidylglycerol (PG), phosphatidylethanolamine (PE), phosphatidylcholine (PC), diphosphatidylglycerol (DPG), an unidentified lipid (L), and three unidentified phospholipids (PL1-PL3). Based on the draft genome sequence, the DNA G + C content of the strain was 67.1 mol%, and the values of average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) of strain YIM 132242T with Paracoccus aerius KCTC 42845T were 85.4% and 29.1%, respectively. On the basis of the data from this polyphasic characterization, strain YIM 132242T represents a novel species of the genus Paracoccus, for which the name Paracoccus lichenicola sp. nov. is proposed. The type strain is YIM 132242T (= KCTC 72463T = CGMCC1.17191T).

Methylobacterium planium sp. nov., isolated from a lichen sample.

A novel bacterial strain, designated YIM 132548 T, was isolated from Lepraria sp. lichen collected from Yunnan province, south-west PR China. The organism was Gram-stain negative, aerobic and methylotrophic. The cell was catalase positive and oxidase negative, asporogenous, rod-shaped and motile with three polar flagella. The strain could grow at 15-30 °C (optimum, 20 °C), at pH 6.0-9.0 (optimum, pH 7.0) and does not grow in the presence of NaCl. According to the 16S rRNA gene sequence analysis, strain YIM 132548 T showed high levels of 16S rRNA gene sequence similarity with Methylobacterium soli YIM 48816 T (97.6%) and Methylobacterium durans NBRC 112876 T (97.3%), less than 97.0% with other validly named type strains of the genus Methylobacterium. Ubiquinone Q-10 was the predominant respiratory ubiquinone. The predominant cellular fatty acid was identified as summed feature 8 (C18:1ω7c). The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. The DNA G + C content of the draft genome sequence is 70.2 mol%. The average nucleotide identity and digital DNA-DNA hybridizations values of strain YIM 132548 T with M. soli YIM 48816 T and M. durans NBRC 112876 T were 87.0% and 82.0%, 40.6% and 27.2% based on draft genome sequences, respectively. On the basis of phylogenetic, chemotaxonomic, phenotypic and genomic data, strain YIM 132548 T is concluded to represent a novel species of the genus Methylobacterium, for which the name Methylobacterium planium sp. nov. is proposed. The type strain is YIM 132548 T (= CGMCC 1.17323 T = NBRC 114056 T).

Naasia lichenicola sp. nov., an actinobacterium isolated from lichen.

A Gram-stain-positive, yellow-pigmented, catalase-positive and oxidase-negative, strictly aerobic actinobacterium, designated strain YIM 131853T, was isolated from lichen collected from the South Bank of the Baltic Sea. The novel strain was non-spore-forming, short rod-shaped and motile with a single polar flagellum. The strain could grow at 4-37 °C (optimum, 28 °C), at pH 4.0-12.0 (pH 6.0) and at 0-3 % (w/v) NaCl (1 %). The DNA G+C content of strain YIM 131853T based on the draft genome sequence was 68.3 mol%. Predominant cellular fatty acids (>10 %) were identified as anteiso-C15 : 0, anteiso-C17 : 0 and iso-C16 : 0. The polar lipid profile included diphosphatidylglycerol, dimannosyldiacylglycerol, three unknown glycolipids, two unknown phospholipids and one unknown lipid. Strain YIM 131853T had 2,4-diaminobutyric acid as the diagnostic cell-wall diamino acid, galactose and glucose as whole-cell sugars, and MK-10, MK-14, MK-13 and MK-12 as the major menaquinones. Although strain YIM 131853T exhibited a highest 16S rRNA gene sequence similarity (96.6 %) to Amnibacterium kyonggiense NBRC 109360T, phylogenetic analysis based on 16S rRNA gene sequences indicated that the strain formed a tight lineage with Naasia aerilata NBRC 108725T (96.5 % 16S rRNA gene sequence similarity), which was the only species of genus Naasia. Based on the results of phenotypic, chemotaxonomic and phylogenetic analyses, strain YIM 131853T should belong to the genus Naasia and represents a novel species of the genus Naasia, for which the name Naasia lichenicola sp. nov. is proposed. The type strain is YIM 131853T (=CGMCC 4.7565T=NBRC 113605T).

Circ_0001658 promotes the proliferation and metastasis of osteosarcoma cells via regulating miR-382-5p/YB-1 axis.

Circular RNA (circRNA) can modulate the gene expression via sponging microRNA (miRNA) in multiple malignancies. Nevertheless, the detailed function of circ_0001658 in osteosarcoma (OS) and its regulatory mechanism remain elusive. Real-time PCR was carried out to detect the expressions of circ_0001658, miR-382-5p, and Y box-binding protein 1 (YB-1) mRNA in OS tissues. Besides, western blot was done to monitor YB-1 expression in OS cells. Chi-squared test was used to analyse the correlation between circ_0001658 and clinicopathologic characteristics of OS patients. CCK8 assay, colony formation assay, flow cytometry, and transwell assay were performed to determine the function of circ_0001658. Moreover, dual-luciferase reporter gene assay was done to verify the targeting relationship between circ_0001658 and miR-382-5p. Compared with adjacent tissues, circ_0001658 displayed a significantly higher expression in OS tissues. Circ_0001658 could facilitate the proliferation, migration, and invasion of OS cells and impede apoptosis by sponging miR-382-5p. Further, circ_0001658 was proved to directly and negatively regulate the expression of miR-382-5 while positively modulate the expression of YB-1. Circ_0001658 promotes the proliferation and metastasis of OS cells via modulating miR-382-5p/YB-1 axis. SIGNIFICANCE OF THE STUDY: In recent years, the expression and function of circular RNA in cancer have been the focus of tumour research. The study on circular RNA helps elucidate the molecular pathology of tumorigenesis and cancer progression. This study demonstrated that circ_0001658 promotes the proliferation and metastasis of OS cells via modulating miR-382-5p/YB-1 axis. To our best knowledge, this work is the first to study the expression and function of circ_0001658 in cancer.

Aureimonas leprariae sp. nov., Isolated from a Lepraria sp. Lichen.

A Gram-negative, motile, aerobic and coccoid rod-shaped bacterium, designated strain YIM132180T, was isolated from a Lepraria sp. lichen collected from Pu'er, Yunnan Province, China. The strain grew at 15-35 °C (optimum, 25-28 °C), at 0-2% (w/v) NaCl (optimum, 0-1%) and at pH 6.0-9.0 (optimum, pH 7.0). The 16S rRNA gene sequence showed that strain YIM132180T had highest similarity (96.4%) with Aureimonas endophytica 2T4P-2-4T, followed by Aureimonas ureilytica NBRC 106430T (95.7%) and Aureimonas rubiginis CC-CFT034T (95.6%). Phylogenetic analysis showed that the strain grouped with species of the genus Aureimonas. The genomic sequence was 4,779,519 bp and contained 4584 coding sequences (CDSs), 54 RNA genes, 3 complete rRNA genes and 47 tRNA genes. The major fatty acids (>10%) of strain YIM132180T were C18:1ω7c, C-16:0 and C19:0 cyclo ω8c. The predominant menaquinone was ubiquinone 10 (Q-10). The polar lipid profile comprised diphosphatidylglycerol, phosphatidylcholine, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylglycerol, unidentified phospholipid, amino lipid, lipid and most importantly sulfoquinovosyldiacylglycerol (SQDG). Based on the draft genome sequence, the G +C content of strain YIM132180T was 68.4 mol%. The results of the polyphasic taxonomic study, including phenotypic, chemotaxonomic, and phylogenetic analyses, showed that strain YIM132180T represents a novel species of the genus Aureimonas, for which the name Aureimonas leprariae sp. nov. is proposed. The type strain is YIM 132180T (=KCTC 72462T = CGMCC 1.17389T).

Nakamurella albus sp. nov.: A Novel Actinobacterium Isolated from a Lichen Sample.

A novel actinobacterium, YIM 132087T, isolated from Lepraria sp. lichen collected from Yunnan province, south-west PR China. Cells are Gram-stain-positive, catalase-positive and oxidase-negative, aerobic, non-motile and short rod-shaped. Colonies are asporogenous, circular and white brown in colour. Optimal growth occured at 15-35 °C (optimum 28 °C), at pH 5.0-9.0 (optimum pH 6.0), and in the presence of 3% NaCl (w/v). The DNA G+C content of strain YIM 132087T based on the draft genome sequence was 71.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences suggested that strain YIM 132087T belonged to the genus Nakamurella and exhibited high levels of 16S rRNA gene sequence similarity with Nakamurella endophytica CGMCC 4.7038T (97.9%) and Nakamurella intestinalis NBRC 111844T (97.2%). The DNA-DNA hybridization values between strain YIM 132087T and its closest relatives are lower than 26%. Strain YIM 132087T had meso-diaminopimelic acid as the diagnostic cell-wall diamino acid, and MK-8(H4) as the predominant menaquinone. Predominant cellular fatty acids (> 10%) were iso-C16:0, iso-C15:0, C16:0 and anteiso-C15:0. The polar lipid profile were found to be diphosphatidylglycerol, phosphatidylmethylethanolamine, phosphatidylethanolamine, phosphatidylinositol, three unknown phospholipids, one unknown aminophospholipid and one unknown lipid. Based on phenotypic, phylogenetic and chemotaxonomic analysis, strain YIM 132087T belongs to the genus Nakamurella and represents a novel species of the genus Nakamurella, for which the name Nakamurella albus sp. nov., with type strain YIM 132087T (=CGMCC 4.7629T =NBRC 114017T), is proposed.

MicroRNA-193a-5p exerts a tumor suppressor role in glioblastoma via modulating NOVA1.

BACKGROUND AND OBJECTIVES: Glioblastoma (GBM) is the most common and lethal of intracranial tumors, which is characterized by extensive proliferation and the diffused invasion of tumor cells. MicroRNA-193a-5p (miR-193a-5p) have been demonstrated previously as a functional suppressor in the development and progression of various cancers. The current study aimed to investigate whether miR-193a-5p influences cell proliferation and migration through the mitogen-activated protein kinase/extracellular signal-regulated kinase signaling pathway by targeting neuro-oncological ventral antigen 1 (NOVA1) in glioblastoma. MATERIALS AND METHODS: The miR-193a-5p expression was detected by quantitative real-time polymerase chain reaction assay in GBM tissues and cell lines. Cell Counting Kit-8 assay, colony formation analysis, wound-healing, and transwell invasion assays were performed to evaluate cell proliferation, colony formation, migration, and invasion, respectively. Western blot analysis and luciferase reporter gene assay were performed to verify the downstream target gene of miR-193a-5p. RESULTS: The expression of miR-193a-5p was significantly downregulated in GBM tissues and cell lines. Kaplan-Meier analysis showed that patients with low miR-193a-5p expression had a shorter disease-free survival (P < 0.05). Functionally, miR-193a-5p overexpression dramatically suppressed the proliferation, colony formation, migration, and invasion in glioma cells. Bioinformatics prediction and a luciferase assay confirmed that NOVA1 was a direct functional target of miR-193a-5p. Moreover, ectopic expression of NOVA1 could partially reverse the inhibitory effects of miR-193a-5p on glioma cell proliferation, colony formation, migration, and invasion. NOVA1 overexpression abrogated the inhibitory effect of miR-193a-5p on the PTEN/PI3k/AKT pathway. CONCLUSION: Taken together, our findings suggested that miR-193a-5p functions as a tumor suppressor in glioma cells by directly targeting NOVA1.

Rubellimicrobium rubrum sp. nov., a novel bright reddish bacterium isolated from a lichen sample.

A novel strain, YIM 131921T, was isolated from a Physcia sp. lichen collected from the South Bank Forest of the Baltic Sea. The strain is Gram-negative, catalase positive and oxidase negative, strictly aerobic, asporogenous, non-motile and reddish brown in colour. The temperature and pH for growth were found to be 20-30 °C (optimum 28 °C) and pH 6.5-12.0 (optimum pH 7.0 ± 0.5). No growth was observed in the presence of NaCl. Based on 16S rRNA gene sequence similarity, strain YIM 131921T shares high similarities with Rubellimicrobium roseum YIM 48858T (98.3%), followed by Rubellimicrobium mesophilum MSL-20T (96.8%), Rubellimicrobium aerolatum 5715S-9T (96.1%) and Rubellimicrobium thermophilum DSM 16684T (96.0%). Phylogenetic trees showed YIM 131921T forms a cluster with type strains of the genus Rubellimicrobium. The predominant cellular fatty acids (> 20%) were identified as summed feature 8 (C18:1ω7c) and C16:0. Q-10 was found to be the predominant respiratory ubiquinone. The polar lipids were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, glycolipid, phospholipids and an unidentified aminolipid. The DNA G + C content of the draft genome sequence is 66.6 mol%. Strain YIM 131921T showed an average nucleotide identity value of 80.3% and a digital DNA-DNA hybridizations value of 26.1% with the reference strain R. roseum YIM 48858T based on draft genome sequences. Based on comparative analyses of phenotypic, molecular, chemotaxonomic data and genomic comparisons, strain YIM 131921T is concluded to represent a novel species of the genus Rubellimicrobium, for which the name Rubellimicrobium rubrum sp. nov. is proposed. The type strain is YIM 131921T (= CGMCC 1.13958T = NBRC 114054T = KCTC 72461T).

Diversity, Antimicrobial Activity, and Biosynthetic Potential of Cultivable Actinomycetes Associated with Lichen Symbiosis.

Lichens are structured associations of a fungus with a cyanobacteria and/or green algae in a symbiotic relationship, which provide specific habitats for diverse bacterial communities, including actinomycetes. However, few studies have been performed on the phylogenetic relationships and biosynthetic potential of actinomycetes across lichen species. In the present study, a total of 213 actinomycetes strains were isolated from 35 lichen samples (22 lichen genera) collected in Yunnan Province, China. 16S rRNA gene sequence analysis revealed an unexpected level of diversity among these isolates, which were distributed into 38 genera, 19 families, and 9 orders within the Actinobacteria phylum. The detailed taxa of isolates had no clear relationship to the taxonomic affiliations of the associated lichens. To the best of our knowledge, this is the first report to describe the isolation of Actinophytocola, Angustibacter, Herbiconiux, Kibdelosporangium, Kineosporia, Kitasatospora, Nakamurella, Nonomuraea, Labedella, Lechevalieria, Lentzea, Schumannella, and Umezawaea species from lichens. At least 40 isolates (18.78%) are likely to represent novel actinomycetes taxa within 15 genera. In addition, all 213 isolates were tested for antimicrobial activity and screened for genes associated with secondary metabolite production to evaluate their biosynthetic potential. These results demonstrate that the lichens of Yunnan Province represent an extremely rich reservoir for the isolation of a significant diversity of actinomycetes, including novel species, which are potential source for discovering biologically active compounds.

Gypmacrophin A, a Rare Pentacyclic Sesterterpenoid, Together with Three Depsides, Functioned as New Chemical Evidence for Gypsoplaca macrophylla (Zahlbr.) Timdal Identification.

The phytochemical investigation on 1 g of materials from Gypsoplacamacrophylla (Zahlbr.) Timdal resulted in the discovery of gypmacrophin A, a rare pentacyclic sesterterpenoid; brialmontin III, a new polysubstituted depside and two known ones, brialmontins I and II. The structure and absolute configurations of gypmacrophin A were elucidated by spectroscopic analyses and computational methods. Gypmacrophin A showed weak inhibition of AchE with an IC50 value of 32.03 µM. The four compounds provided new chemical evidence for G. macrophylla identification.

Who's getting around? Assessing species diversity and phylogeography in the widely distributed lichen-forming fungal genus Montanelia (Parmeliaceae, Ascomycota).

Brown parmelioid lichens comprise a number of distinct genera in one of the most species-rich families of lichen-forming fungi, Parmeliaceae (Ascomycota). In spite of their superficial similarity, a number of studies of brown parmelioids have provided important insight into diversification in lichen-forming fungi with cosmopolitan distributions. In this study we assess species diversity, biogeography and diversification of the genus Montanelia, which includes alpine to temperate saxicolous species. We sampled each of the five known species, four of which are known from broad, intercontinental distributions. In order to identify potential biogeographical patterns, each broadly distributed species was represented by individuals collected across their intercontinental distributions. Molecular sequence data were generated for six loci, including three nuclear protein-coding markers (MCM7, RPB1, and RPB2), two nuclear ribosomal markers (ITS and nrLSU), and a fragment of the mitochondrial small subunit. We used three sequence-based species delimitations methods to validate traditional, phenotype-based species and circumscribe previously unrecognized species-level lineages in Montanelia. Relationships among putative lineages and divergence times were estimated within a coalescent-based multi-locus species tree framework. Based on the results of the species delimitation analyses, we propose that the genus Montanelia is likely comprised of six to nine species-level lineages, including previously unrecognized species-level diversity in the nominal taxa M. panniformis and M. tominii. In contrast, molecular sequence data suggest that M. predisjuncta may be conspecific with the widespread taxon M. disjuncta in spite of distinct morphological differences. The rate-based age estimation of the most recent common ancestor of Montanelia (ca. 23.1Ma) was similar to previous estimates based on the fossil record. Furthermore, our data suggest that diversification in Montanelia occurred largely during the Neogene. At least three Montanelia species are broadly distributed throughout Asia, Europe, and North America with no evidence of phylogeographic substructure. In contrast to broadly distributed Montanelia species, our study suggests Pleistocene-dominated diversification and complex biogeographic history in the M. tominii group. Our analyses provide additional insight for understanding diversification and uncovering cryptic diversity in cosmopolitan species of lichen-forming fungi.

Two new species of Rhizoplaca (Lecanoraceae) from Southwest China.

In this study, two new species, Rhizoplacaadpressa Y. Y. Zhang & Li S. Wang and R.auriculata Y. Y. Zhang, Li S. Wang & Printzen, are described from Southwest China, based on their morphology, phylogeny and chemistry. In phylogeny, the two new species are monophyletic, and sister to each other within Rhizoplacachrysoleuca-complex. Rhizoplacaadpressa is characterized by its placodioid and closely adnate thallus, pale green and heavily pruinose upper surface, narrow (ca. 1 mm) and white free margin on the lower surface of marginal squamules, the absence of a lower cortex, and its basally non-constricted apothecia with orange discs that turn reddish-brown at maturity. Rhizoplacaauriculata is characterized by its squamulose to placodioid thallus, yellowish green and marginally pruinose squamules, wide (1-3 mm) and bluish-black free margin on the lower surface of marginal squamules, the absence of a lower cortex, and its basally constricted apothecia with persistently orange discs. Rhizoplacaadpressa and R.auriculata share the same secondary metabolites of usnic and placodiolic acids.

Unveiling the therapeutic potential of Lobaria extract and its depsides/depsidones in combatting Aß42 peptides aggregation and neurotoxicity in Alzheimer's disease.

Background: The development of effective inhibitors that can inhibit amyloid ß (Aß) peptides aggregation and promote neurite outgrowth is crucial for the possible treatment of Alzheimer's disease (AD). Lobaria (Schreb.) Hoffm., a traditional Chinese medicine used in Himalaya region for inflammatory diseases, contains depsides/depsidones (DEPs) such as gyrophoric acid, norstictic acid, and stictic acid known for their anti-cancer and anti-inflammation properties. Methods: Lobaria extracts were analyzed using HPLC to identify DEPs and establish standards. The inhibitory effects of Lobaria on Aß42 fibrillization and depolymerization were assessed using various approaches with biophysical and cellular methods. The neuroprotective activity of Lobaria extracts and its DEPs aganist Aß-mediated cytotoxicity was also evaluated. Results: Norstictic and stictic acid were found in the water extract, while norstictic, stictic, and gyrophoric acid were detected in the ethanol extract of Lobaria. Both extracts, and their DEPs effectively inhibited Aß42 fibrillation and disaggregate mature Aß42 fibrils. Notably, the ethanol extract showed superior inhibitory effect compared to the water extract, with gyrophoric acid being the most effective DEPs. Additionally, herbal extract-treated Aß42 aggregation species significantly protected neuronal cells from Aß42-induced cell damage and promoted neurite outgrowth. Conclusion: This study is the first to investigate the effect of Lobaria on Aß42 and neuronal cell in AD. Given that Lobaria is commonly used in ethnic medicine and food with good safety records, our findings propose that Lobaria extracts and DEPs have potential as neuroprotective and therapeutic agents for AD patients.