Lutimonas zeaxanthinifaciens sp. nov., a zeaxanthin-producing marine bacterium isolated from coastal sediment.

A Gram-stain-negative, yellow-pigmented, strictly aerobic, non-flagellated, motile by gliding, rod-shaped bacterium, designated strain YSD2104T, was isolated from a coastal sediment sample collected from the southeastern part of the Yellow Sea. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that strain YSD2104T was closely related to three type strains, Lutimonas vermicola IMCC1616T (97.4 %), Lutimonas saemankumensis SMK-142T (96.9 %), and Lutimonas halocynthiae RSS3-C1T (96.8 %). Strain YSD2104T has a single circular chromosome of 3.54 Mbp with a DNA G+C content of 38.3 mol%. The average nucleotide identity and digital DNA-DNA hybridization values between strain YSD2104T and the three type strains (L. vermicola IMCC1616 T, L. saemankumensis SMK-142T, and L. halocynthiae RSS3-C1T) were 74.0, 86.2 and 73.6 %, and 17.9, 30.3 and 17.8 %, respectively. Growth was observed at 20-30 °C (optimum, 30 °C), at pH 6.5-8.5 (optimum, pH 7.0), and with NaCl concentrations of 1.5-3.5 % (optimum, 2.5 %). The major carotenoid was zeaxanthin, and flexirubin-type pigment was not produced. The major respiratory quinone was menaquinone-6. The major fatty acids (>10 %) were iso-C15 : 0, iso-C15 : 1 G, iso-C17 : 0 3-OH, summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c), and summed feature 9 (iso-C17 : 1 ω9c and/or 10-methyl C16 : 0). The major polar lipids were phosphatidylethanolamine, one unidentified aminophospholipid, two unidentified aminolipids, and eight unidentified lipids. Conclusively, based on this polyphasic approach, we classified strain YSD2104T (=KCTC 102008T=JCM 36287T) as representing a novel species of the genus Lutimonas and proposed the name Lutimonas zeaxanthinifaciens sp. nov.

Identification and characterization of a marine bacterium extract from Mameliella sp. M20D2D8 with antiviral effects against influenza A and B viruses.

Despite significant improvements in vaccines and chemotherapeutic drugs, pathogenic RNA viruses continue to have a profound impact on the global economy and pose a serious threat to animal and human health through emerging and re-emerging outbreaks of diseases. To overcome the challenge of viral adaptation and evolution, increased vigilance is required. Particularly, antiviral drugs derived from new, natural sources provide an attractive strategy for controlling problematic viral diseases. In this antiviral study, we discovered a previously unknown bacterium, Mameliella sp. M20D2D8, by conducting an antiviral screening of marine microorganisms. An extract from M20D2D8 exhibited antiviral activity with low cytotoxicity and was found to be effective in vitro against multiple influenza virus strains: A/PR8 (IC50 = 2.93 µg/mL, SI = 294.85), A/Phil82 (IC50 = 1.42 µg/mL, SI = 608.38), and B/Yamagata (IC50 = 1.59 µg/mL, SI = 543.33). The antiviral action was found to occur in the post-entry stages of viral replication and to suppress viral replication by inducing apoptosis in infected cells. Moreover, it efficiently suppressed viral genome replication, protein synthesis, and infectivity in MDCK and A549 cells. Our findings highlight the antiviral capabilities of a novel marine bacterium, which could potentially be useful in the development of drugs for controlling viral diseases.

Falsirhodobacter algicola sp. nov., a member of the Rhodobacteraceae isolated from the marine red algae Grateloupia sp.

A Gram-negative, pale yellow-pigmented, non-flagellated, motile, rod-shaped and aerobic bacterium, designated strain PG104T, was isolated from red algae Grateloupia sp. collected from the coastal area of Pohang, Republic of Korea. Growth of strain PG104T was observed at 15-35 °C (optimum, 30 °C), pH 6.0-10.0 (optimum, pH 7.5-8.0) and in the presence of 0-8.0 % (w/v) NaCl (optimum, 5.0 %). The predominant fatty acids included C17 : 0, C18 : 0, 11-methyl C18 : 1 ω7c and summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) and the major respiratory quinone was Q-10. Polar lipids included phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol, one unidentified lipid and one unidentified aminolipid. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that strain PG104T formed a phylogenetic lineage with members of the genus Falsirhodobacter and exhibited 16S rRNA gene sequence similarities of 97.1 and 96.6 % to Falsirhodobacter deserti W402T and Falsirhodobacter halotolerans JA744T, respectively. The complete genome of strain PG104T consisted of a single circular chromosome of approximately 2.8 Mbp with five plasmids. Based on polyphasic taxonomic data, strain PG104T represents a novel species in the genus Falsirhodobacter, for which the name Falsirhodobacter algicola sp. nov. is proposed. The type strain of Falsirhodobacter algicola is PG104T (=KCTC 82230T=JCM 34380T).

Fulvivirga lutea sp. nov., a marine bacterium isolated from seawater.

A strictly aerobic, Gram-stain-negative, gliding, rod-shaped bacteria, designated strain S481T, was isolated from a surface seawater sample collected at Gunsan marina, in the West Sea of the Republic of Korea. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain S481T formed a monophyletic clade with members of the genus Fulvivirga, showing 93.7-95.8% sequence similarity to the type strains. Strain S481T has a single circular chromosome of 4.13 Mbp with a DNA G+C content of 37.3 mol%. The values of average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization between strain S481T and all genome-sequenced species of the genus Fulvivirga were below 71.2%, 68.6% and 18.9%, respectively, indicating lower values than the standard cut-offs for species delineation. Growth was observed at 20-42 °C (optimum, 37 °C), at pH 6-8 (optimum, pH 7) and with 0 - 6 % NaCl (optimum, 1-2 %). The major fatty acids (>10%) were iso-C15:0, iso-C15:1 G and C16:1ω5c. The respiratory quinone was MK-7. The major polar lipids were identified as phosphatidylethanolamine, three unidentified aminolipids and five unidentified lipids. Based on the results of phenotypic characterization, phylogenetic analysis and genome-based comparison, strain S481T represents a novel species in the genus Fulvivirga, for which we propose the name Fulvivirga lutea sp. nov. The type strain is S481T (=KCTC 82209T=JCM 34505T).

Aggregatimonas sangjinii gen. nov., sp. nov., a novel silver nanoparticle synthesizing bacterium belonging to the family Flavobacteriaceae.

Microbially synthesized nanoparticles has received increasing attentions owing to the broad applications in biology and medicine. In this study, we report a novel bacterium that biologically generates silver nanoparticles (AgNPs). This bacterium, designated strain F202Z8T, was isolated from a rusty iron plate found in the intertidal region of Taean, South Korea. The morphological, biochemical and molecular characteristics predicted that strain F202Z8T belongs to the family Flavobacteriaceae. Phylogenetic analysis based on 16S rRNA gene sequence revealed that strain F202Z8T forms a distinct lineage with closely related genera Maribacter, Pelagihabitans, Pseudozobellia, Zobellia, Pricia, and Costertonia and showed the highest similarity to Maribacter aestuarii GY20T (94.5%). The digital DNA-DNA hybridization and average nucleotide identity values calculated from the whole genome-sequence comparison between strain F202Z8T and other members of the family Flavobacteriaceae were in the ranges of 12.7%-16.9% and 70.3%-74.4%, respectively, suggesting that strain F202Z8T represented a novel genus. The complete genome sequence of strain F202Z8T is 4,723,614 bp, with 43.26% G + C content. Based on the COG, GO, KEGG, NR, and Swiss-Prot databases, the genomic analysis of F202Z8T revealed the presence of 17 putative genes responsible for the synthesis of AgNPs. Our polyphasic taxonomic results suggested that this strain represents a novel species of a novel genus in the family Flavobacteriaceae, for which the name Aggregatimonas sangjinii gen. nov., sp. nov. is proposed. The type strain of Aggregatimonas sangjinii is F202Z8T (= KCCM 43411T = LMG 31494T). Overall, our data provide fundamental information to potentially utilize this novel bacterium for synthesis of nanoparticles.

Telomere-to-telomere genome assembly of asparaginase-producing Trichoderma simmonsii.

BACKGROUND: Trichoderma is a genus of fungi in the family Hypocreaceae and includes species known to produce enzymes with commercial use. They are largely found in soil and terrestrial plants. Recently, Trichoderma simmonsii isolated from decaying bark and decorticated wood was newly identified in the Harzianum clade of Trichoderma. Due to a wide range of applications in agriculture and other industries, genomes of at least 12 Trichoderma spp. have been studied. Moreover, antifungal and enzymatic activities have been extensively characterized in Trichoderma spp. However, the genomic information and bioactivities of T. simmonsii from a particular marine-derived isolate remain largely unknown. While we screened for asparaginase-producing fungi, we observed that T. simmonsii GH-Sj1 strain isolated from edible kelp produced asparaginase. In this study, we report a draft genome of T. simmonsii GH-Sj1 using Illumina and Oxford Nanopore technologies. Furthermore, to facilitate biotechnological applications of this species, RNA-sequencing was performed to elucidate the transcriptional profile of T. simmonsii GH-Sj1 in response to asparaginase-rich conditions. RESULTS: We generated ~ 14 Gb of sequencing data assembled in a ~ 40 Mb genome. The T. simmonsii GH-Sj1 genome consisted of seven telomere-to-telomere scaffolds with no sequencing gaps, where the N50 length was 6.4 Mb. The total number of protein-coding genes was 13,120, constituting ~ 99% of the genome. The genome harbored 176 tRNAs, which encode a full set of 20 amino acids. In addition, it had an rRNA repeat region consisting of seven repeats of the 18S-ITS1-5.8S-ITS2-26S cluster. The T. simmonsii genome also harbored 7 putative asparaginase-encoding genes with potential medical applications. Using RNA-sequencing analysis, we found that 3 genes among the 7 putative genes were significantly upregulated under asparaginase-rich conditions. CONCLUSIONS: The genome and transcriptome of T. simmonsii GH-Sj1 established in the current work represent valuable resources for future comparative studies on fungal genomes and asparaginase production.

Ferrimonas lipolytica sp. nov., a facultatively anaerobic bacterium isolated from seawater.

A Gram-stain-negative, motile, facultatively anaerobic rod-shaped bacterium with a polar flagellum, designated strain S7T was isolated from seawater sample collected at Uljin marina, in the East Sea of the Republic of Korea. Phylogenetic analysis based on the 16S rRNA gene sequences revealed that strain S7T was affiliated with members of genus Ferrimonas, showing the highest sequence similarities to the type strains Ferrimonas senticii P2S11T (95.7 %), Ferrimonas balearica PATT (95.7 %) and Ferrimonas pelagia CBA4601T (95.1 %). The genome was 4.13 Mbp with a DNA G+C content of 49.4 %. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) between S7T and F. senticii P2S11T and F. balearica PATT yielded ANI values of 71.9 and 70.7 %, and dDDH values of 15.1 and 13.9 %, respectively. The genome of S7T was predicted to encode triacylglycerol lipase, phospholipase A1/A2 and lysophospholipase as well as esterase involved in lipolytic processes. Growth was observed at 8-31 °C (optimum 27 °C), at pH 7-9 (optimum pH 7), and with 1-6 % NaCl (optimum 2 %). The respiratory quinones were MK-7 and Q-7 and the major fatty acids (>10 %) were C16 : 0, C16 : 1ω9c, C17 : 1ω8c, and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c). The major polar lipids were identified as phosphatidylethanolamine, phosphatidylglycerol, two unidentified phospholipids, and three unidentified lipids. On the basis of the results of this polyphasic analysis, it was determined that the strain represents a novel species of the genus Ferrimonas, for which the name Ferrimonas lipolytica sp. nov. is proposed. The type strain is S7T (=KCTC 72490T=JCM 33793T).

Nonlabens ponticola sp. nov., isolated from seawater and reclassification of Nonlabens sediminis as a later heterotypic synonym of Nonlabens tegetincola.

A Gram-stain-negative, orange-pigmented and strictly aerobic bacterium, designated strain MJ115T, was isolated from seawater in Pohang, South Korea. Cells were non-motile rods and showed positive reactions for catalase and oxidase tests. Growth of strain MJ115T was observed at 4-35 °C (optimum, 30 °C), pH 6.0-7.0 (optimum, pH 6.5) and in the presence of 0-8.0 % (w/v) NaCl (optimum, 2.0%). Strain MJ115T contained iso-C15 : 0, anteiso-C15 : 0, anteiso-C17 : 1 ω9c, C17 : 0 2-OH, iso-C16 : 0 3-OH, iso-C17 : 0 3-OH and summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) as major cellular fatty acids and menaquinone-6 as the major respiratory quinone. Phosphatidylethanolamine, two unidentified aminolipids and four unidentified lipids were detected as major polar lipids. The G+C content of the genomic DNA was 40.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain MJ115T formed a phyletic lineage with Nonlabens marinus S1-08T, Nonlabens agnitus JC2678T and Nonlabens antarcticus AKS 622T within the genus Nonlabens. Strain MJ115T was also most closely related to N. marinus S1-08T, N. agnitus JC2678T and N. antarcticus AKS 622T with 96.5, 96.4 and 96.0 % 16S rRNA sequence similarities, respectively. Here it is proposed that strain MJ115T represents a new species of the genus Nonlabens, for which the name Nonlabens ponticola sp. nov. is proposed. The type strain is MJ115T (=KCTC 72237T=NBRC 113963T). In addition, the comparison of the whole genome sequences and phenotypic features suggested that Nonlabens tegetincola and Nonlabens sediminis belong to the same species. Therefore, it is proposed that N. sediminis is reclassified as a later heterotypic synonym of N. tegetincola.

Exploring the Potential of Nannochloropsis sp. Extract for Cosmeceutical Applications.

Recently, there has been emerging interest in various natural products with skin protective effects as they are recognized as safe and efficient. Microalgae have developed chemical defense systems to protect themselves against oxidative stress caused by UV radiation by producing various bioactive compounds including a number of secondary metabolites, which have potential for cosmeceutical applications. In addition, microalgae have various advantages as a sustainable source for bioactive compounds with diverse functions due to their rapid growth rate, high productivity, and use of non-arable land. In this study, we aimed to investigate the cosmeceutical potential of ethanol extract from Nannochloropsis sp. G1-5 (NG15) isolated from the southern West Sea of the Republic of Korea. It contained PUFAs (including EPA), carotenoids (astaxanthin, canthaxanthin, ß-carotene, zeaxanthin, violaxanthin), and phenolic compounds, which are known to have various skin protective functions. We confirmed that the NG15 extract showed various skin protective functions with low cytotoxicity, specifically anti-melanogenic, antioxidant, skin-moisturizing, anti-inflammatory, anti-wrinkling, and UV protective function, by measuring tyrosinase inhibition activity; melanin content; DPPH radical scavenging activity; expression of HAS-2, MMP-1, and Col1A1 genes; and elastase inhibition activity as well as cell viability after UV exposure. Our results indicated that the NG15 extract has the potential to be used for the development of natural cosmetics with a broad range of skin protective functions.

Euzebyella algicola sp. nov., a marine bacterium of the family Flavobacteriaceae, isolated from green algae.

A Gram-negative, yellow-pigmented, non-flagellated, gliding, rod-shaped and aerobic bacterium, designated MEBiC 12267T, was isolated from green algae of Jeju Island. 16S rRNA gene sequence analysis revealed that the strain MEBiC 12267T was affiliated to the genus Euzebyella of the family Flavobacteriaceae and showed the highest similarity to Euzebyella marina KCTC 42440T (98.5 %). The DNA-DNA relatedness value of strain MEBiC 12267T with E. marina KCTC 42440T was 25 %. Growth was observed at 10-37 °C (optimum, 30-33 °C), at pH 6.0-9.5 (optimum, 8.0-8.5) and with 0.5-9.0 % (w/v) NaCl (optimum, 2.5-3.5 %). The predominant cellular fatty acids were iso-C15 : 0, iso-C15 : 1 G and iso-C17 : 0 3-OH. The major respiratory quinone was MK-6. Polar lipids included phosphatidylethanolamine, seven unidentified lipids and two unidentified aminolipids. The DNA G+C content was 40.7 mol%. On the basis of the data from the polyphasic taxonomic study, it was concluded that the strain MEBiC 12267T represents a novel species within the genus Euzebyella, for which the name Euzebyella algicola sp. nov. is proposed. The type strain of E. algicola is MEBiC 12267T (=KCCM 43264T=JCM 32170T).

Manipulation of the microalgal chloroplast by genetic engineering for biotechnological utilization as a green biofactory.

The chloroplast is an essential organelle in microalgae for conducting photosynthesis, thus enabling the photoautotrophic growth of microalgae. In addition to photosynthesis, the chloroplast is capable of various biochemical processes for the synthesis of proteins, lipids, carbohydrates, and terpenoids. Due to these attractive characteristics, there has been increasing interest in the biotechnological utilization of microalgal chloroplast as a sustainable alternative to the conventional production platforms used in industrial biotechnology. Since the first demonstration of microalgal chloroplast transformation, significant development has occurred over recent decades in the manipulation of microalgal chloroplasts through genetic engineering. In the present review, we describe the advantages of the microalgal chloroplast as a production platform for various bioproducts, including recombinant proteins and high-value metabolites, features of chloroplast genetic systems, and the development of transformation methods, which represent important factors for gene expression in the chloroplast. Furthermore, we address the expression of various recombinant proteins in the microalgal chloroplast through genetic engineering, including reporters, biopharmaceutical proteins, and industrial enzymes. Finally, we present many efforts and achievements in the production of high-value metabolites in the microalgal chloroplast through metabolic engineering. Based on these efforts and advances, the microalgal chloroplast represents an economically viable and sustainable platform for biotechnological applications in the near future.

Extracellular Vesicles of the Hyperthermophilic Archaeon "Thermococcus onnurineus" NA1T.

Extracellular vesicles (EVs) produced by a sulfur-reducing, hyperthermophilic archaeon, "Thermococcus onnurineus" NA1(T), were purified and characterized. A maximum of four EV bands, showing buoyant densities between 1.1899 and 1.2828 g cm(-3), were observed after CsCl ultracentrifugation. The two major EV bands, B (buoyant density at 25°C [ρ(25)] = 1.2434 g cm(-3)) and C (ρ(25) = 1.2648 g cm(-3)), were separately purified and counted using a qNano particle analyzer. These EVs, showing different buoyant densities, were identically spherical in shape, and their sizes varied from 80 to 210 nm in diameter, with 120- and 190-nm sizes predominant. The average size of DNA packaged into EVs was about 14 kb. The DNA of the EVs in band C was sequenced and assembled. Mapping of the T. onnurineus NA1(T) EV (ToEV) DNA sequences onto the reference genome of the parent archaeon revealed that most genes of T. onnurineus NA1(T) were packaged into EVs, except for an ∼9.4-kb region from TON_0536 to TON_0544. The absence of this specific region of the genome in the EVs was confirmed from band B of the same culture and from bands B and C purified from a different batch culture. The presence of the 3'-terminal sequence and the absence of the 5'-terminal sequence of TON_0536 were repeatedly confirmed. On the basis of these results, we hypothesize that the unpackaged part of the T. onnurineus NA1(T) genome might be related to the process that delivers DNA into ToEVs and/or the mechanism generating the ToEVs themselves.

Neural injury by frontal approach of external ventricular drainage in stroke patients.

OBJECTIVES: No study on the characteristics of injury of neural tracts following external ventricular drainage (EVD) in a large number of consecutive patients following EVD has been reported. In this study, using diffusion tensor tractography (DTT), we attempted to investigate the characteristics of injury of neural tracts associated with EVD using a frontal approach in stroke patients. METHODS: We recruited 43 consecutive hemorrhagic stroke patients with a history of EVD using a frontal approach. Five neural tracts were reconstructed [corticospinal-tract (CST), corticoreticular-pathway (CRP), arcuate-fasciculus (AF), cingulum, and superior-longitudinal-fasciculus (SLF)]. RESULTS: Among five neural tracts, neural injury by EVD was observed on only two neural tracts (the CRP and the cingulum): CRP-seven (16.3%, five patients-partial tearing and two patients-complete discontinuation) of 43 patients and cingulum-eight (18.6%, eight patients-complete discontinuation of the anterior portion of the cingulum) of 43 patients. CONCLUSIONS: It appears that neural injury occurred in a considerable number of patients who underwent EVD; therefore, conduct of further studies on measures to prevent or minimize neural injury by EVD should be encouraged.

Nonlabens antarcticus sp. nov., a psychrophilic bacterium isolated from glacier ice, and emended descriptions of Nonlabens marinus Park et al. 2012 and Nonlabens agnitus Yi and Chun 2012.

A Gram-negative, proteorhodopsin-containing, orange pigmented, rod-shaped and strictly aerobic bacterium, designated strain AKS622(T), was isolated from a glacier core collected from the coast of King George Island, Antarctica. 16S rRNA gene sequence analysis revealed that strain AKS622(T) was affiliated to the genus Nonlabens of the family Flavobacteriaceae and showed highest similarity to Nonlabens marinus S1-08(T) (97.9%). The level of DNA-DNA relatedness between strain AKS622(T) and N. marinus S1-08(T) was 46%. Optimal growth of strain AKS622(T) was observed at pH 7.0, at 15 °C and with 2.0% NaCl. The predominant cellular fatty acids were anteiso-C(15 : 0), iso-C(16 : 0), iso-C(16 : 0) 3-OH, C17:0 2-OH and summed feature 3 (comprising C(16 : 1)ω7c and/or C(16 : 1)ω6c). The DNA G+C content was 37.9 mol%. The major respiratory quinone was MK-6. Phosphatidylethanolamine, four unidentified glycolipids, three unidentified aminolipids and one unidentified lipid were detected as major polar lipids. On the basis of the data from this polyphasic taxonomic study, it was concluded that strain AKS622(T) represents a novel species within the genus Nonlabens, for which the name Nonlabens antarcticus sp. nov. is proposed. The type strain is AKS622(T) ( = KCCM 43019(T) = JCM 14068(T)). Emended descriptions of N. marinus Park et al. 2012 and Nonlabens agnitus Yi and Chun 2012 are given.

Hoppeia youngheungensis gen. nov., sp. nov., a member of the Flavobacteriaceae isolated from tidal flat sediment, and emended descriptions of the genus Sediminibacter and Sediminibacter furfurosus.

A Gram-reaction-negative, proteorhodopsin-containing, yellow-pigmented, rod-shaped, non-gliding and strictly aerobic bacterium, designated strain YIK12(T), was isolated from tidal flat sediment of Yeongheung Island at the coast of the West Sea of Korea. Cells produced non-diffusible carotenoid pigments, but not flexirubin-type pigment. Phylogenetic analyses based on 16S rRNA gene sequences indicated that the isolate was affiliated to the family Flavobacteriaceae and showed highest similarity to Sediminibacter furfurosus MAOS-86(T) (93.3%). Growth was observed at 24-44 °C (optimum 30 °C), at pH 6.5-8.0 (optimum 7.0) and in the presence of 1.5-7.0% sea salts (optimum 2%). The DNA G+C content was 40.4 mol% and the predominant cellular fatty acids were iso-C(15 : 0), iso-C(15 : 1) G, iso-C(17 : 0) 3-OH, iso-C(16 : 0) 3-OH, anteiso-C(15 : 0) and iso-C(15 : 0) 3-OH. The major respiratory quinone was MK-6. On the basis of data from the present polyphasic taxonomic study, strain YIK12(T) is considered to represent a novel species of a new genus in the family Flavobacteriaceae, for which the name Hoppeia youngheungensis gen. nov., sp. nov. is proposed. The type strain of H. youngheungensis is YIK12(T) ( = KCCM 43023(T) = JCM 19488(T)). Emended descriptions of the genus Sediminibacter and Sediminibacter furfurosus are given.

A Noble Extract of Pseudomonas sp. M20A4R8 Efficiently Controlling the Influenza Virus-Induced Cell Death.

Epidemic diseases that arise from infectious RNA viruses, particularly influenza viruses, pose a constant threat to the global economy and public health. Viral evolution has undermined the efficacy of acquired immunity from vaccines and the antiviral effects of FDA-approved drugs. As such, there is an urgent need to develop new antiviral lead agents. Natural compounds, owing to their historical validation of application and safety, have become a promising solution. In this light, a novel marine bacterium, Pseudomonas sp. M20A4R8, has been found to exhibit significant antiviral activity [half maximal inhibitory concentration (IC50) = 1.3 µg/mL, selectivity index (SI) = 919.4] against influenza virus A/Puerto Rico/8/34, surpassing the activity of chloroquine. The antiviral response via M20A4R8 extract was induced during post-entry stages of the influenza virus, indicating suitability for post-application after the establishment of viral infection. Furthermore, post-treatment with M20A4R8 extract protected the host from virus-induced apoptosis, suggesting its potential use in acute respiratory disease complexes resulting from immune effectors' overstimulation and autophagy-mediated self-apoptosis. The extract demonstrated an outstanding therapeutic index against influenza virus A/Wisconsin/15/2009 (IC50 = 8.1 µg/mL, SI = 146.2) and B/Florida/78/2015 Victoria lineage (IC50 = 3.5 µg/mL, SI = 343.8), indicating a broad anti-influenza virus activity with guaranteed safety and effectiveness. This study provides a new perspective on mechanisms for preventing a broad spectrum of viral infections through antiviral agents from novel and natural origins. Future studies on a single or combined compound from the extract hold promise, encouraging its use in preclinical challenge tests with various influenza virus strains.

In vitro and in vivo antimicrobial activity of the fungal metabolite toluquinol against phytopathogenic bacteria.

Introduction: Bacterial plant diseases cause tremendous economic losses worldwide. However, a few effective and sustainable control methods are currently available. To discover novel and effective management approaches, we screened marine fungi for their antibacterial activity against phytopathogenic bacteria in vitro and in vivo. Methods: We screened the culture broth of 55 fungal strains isolated from various marine sources (seawater, algae, and sediment) for their in vitro antibacterial activity using the broth microdilution method. Then, only the fungal strain (designated UL-Ce9) with higher antibacterial activity in vitro was tested in an in vivo experiment against tomato bacterial wilt. The active compounds of UL-Ce9 were extracted using ethyl acetate, purified by a series of chromatography, and the structure was elucidated by nuclear magnetic resonance spectroscopy. Pesticide formulations of toluquinol were prepared as soluble concentrates and wettable powder. The disease control efficacy of toluquinol formulations was evaluated against blight of rice and the bacterial wilt of tomato. Results and discussion: The culture broth of UL-Ce9 showed high antibacterial activity against Agrobacterium tumefaciens, Ralstonia solanacearum, and Xanthomonas arboricola pv. pruni in vitro, and we selected UL-Ce9 for the in vivo test. The UL-Ce9 culture broth completely suppressed the bacterial wilt of tomato at a dilution of 1:5. The phylogenetic analysis identified UL-Ce9 as Penicillium griseofulvum, and the antibacterial metabolites were revealed as patulin, gentisyl alcohol, and toluquinol, all of which were associated with the biosynthetic pathway of the mycotoxin patulin. Patulin exhibited the highest antibacterial activity against 16 phytopathogenic bacteria in vitro, followed by toluquinol and gentisyl alcohol. As patulin is toxic, we selected toluquinol to investigate its potential use as a pesticide against bacterial plant diseases. Compared with the chemicals currently being applied in agriculture (streptomycin and oxytetracycline), toluquinol formulations exhibited similar and higher control efficacies against bacterial leaf blight of rice and bacterial wilt of tomato, respectively. To the best of our knowledge, this is the first report of the antibacterial activity of toluquinol against phytopathogenic bacteria. Our results suggest that toluquinol is a potential candidate for the development of novel and effective pesticides for the management of bacterial plant diseases.

Synthesis of Silver Nanoparticles Using Aggregatimonas sangjinii F202Z8T and Their Biological Characterization.

The aim of this study is to describe the general features and eco-friendly biosynthesis of silver nanoparticles (AgNPs) from the marine bacterium Aggregatimonas sangjinii F202Z8T. To the best of our knowledge, no previous study has reported the biosynthesis of AgNPs using this strain. The formation of AgNPs using F202Z8T was synthesized intracellularly without the addition of any disturbing factors, such as antibiotics, nutrient stress, or electron donors. The AgNPs were examined using UV-vis spectrophotometry, transmission electron microscopy, energy-dispersive X-ray spectroscopy, nanoparticle tracking analysis, and Fourier transform infrared spectrometry. The UV-vis spectrum showed a peak for the synthesized AgNPs at 465 nm. The AgNPs were spherical, with sizes ranging from 27 to 82 nm, as denoted by TEM and NTA. FTIR showed various biomolecules including proteins and enzymes that may be involved in the synthesis and stabilization of AgNPs. Notably, the AgNPs demonstrated broad-spectrum antibacterial effects against various pathogenic Gram-positive and Gram-negative bacteria, including Escherichia coli, Bacillus subtilis, and Staphylococcus aureus. The minimum inhibitory concentrations and minimum bactericidal concentrations of the F202Z8T-formed AgNPs were 80 and 100 µg/mL, 40 and 50 µg/mL, and 30 and 40 µg/mL against E. coli, B. subtilis, and S. aureus, respectively. This study suggests that A. sangjinii F202Z8T is a candidate for the efficient synthesis of AgNPs and may be suitable for the formulation of new types of bactericidal substances.

The complete mitochondrial genome of Trichoderma simmonsii (Hypocreales: Hypocreaceae) from the Southern Coast of Korea.

Fungal species in the genus Trichoderma are widely used for industrial enzyme production and as biocontrol agents. In this study, we report the complete mitochondrial genome of a marine-derived Trichoderma simmonsii strain GH-Sj1, which belongs to the Harzianum clade of Trichoderma. GH-Sj1 was isolated from an edible sea alga Saccharina japonica collected from the southern coast of Korea. This newly assembled circular molecule is 28,668 bp in length and consists of 15 protein-coding genes, 26 transfer RNA genes, and two ribosomal RNA genes. Phylogenetic analysis using the maximum likelihood method shows that T. simmonsii GH-Sj1 is closely related to Trichoderma harzianum and Trichoderma lixii. To the best of our knowledge, this is the first characterization of a marine-derived mitogenome within the genus Trichoderma.

Complete gammaproteobacterial endosymbiont genome assembly from a seep tubeworm Lamellibrachia satsuma.

Siboglinid tubeworms thrive in hydrothermal vent and seep habitats via a symbiotic relationship with chemosynthetic bacteria. Difficulties in culturing tubeworms and their symbionts in a laboratory setting have hindered the study of host-microbe interactions. Therefore, released symbiont genomes are fragmented, thereby limiting the data available on the genome that affect subsequent analyses. Here, we present a complete genome of gammaproteobacterial endosymbiont from the tubeworm Lamellibrachia satsuma collected from a seep in Kagoshima Bay, assembled using a hybrid approach that combines sequences generated from the Illumina and Oxford Nano-pore platforms. The genome consists of a single circular chromosome with an assembly size of 4,323,754 bp and a GC content of 53.9% with 3,624 protein-coding genes. The genome is of high quality and contains no assembly gaps, while the completeness and contamination are 99.33% and 2.73%, respectively. Comparative genome analysis revealed a total of 1,724 gene clusters shared in the vent and seep tubeworm symbionts, while 294 genes were found exclusively in L. satsuma symbionts such as transposons, genes for defense mechanisms, and inorganic ion transportations. The addition of this complete endosymbiont genome assembly would be valuable for comparative studies particularly with tubeworm symbiont genomes as well as with other chemosynthetic microbial communities.