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1.
Plant Dis ; 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448390

RESUMO

In October 2022, typical symptoms of anthracnose were observed on apple (Malus ⅹ domestica cv. Fuji) fruits collected from Pocheon in Gyeonggi province, South Korea (N37.98074°, E127.33995°). In the surveyed orchard, the incidence rate of apple anthracnose was less than 1%. The initial symptoms were brown-to-dark brown lesions, and with disease progression, they enlarged and the pulp became soft, forming a brown band. In total 29 apple fruits were collected, and the causal agent was isolated by removing the peel, and the diseased tissues were directly transferred onto potato dextrose agar (PDA), followed by incubation for 7 days at 25°C. As the results, two isolates (GgPc22-1-11 and GgPc22-1-13) were obtained. For describing morphological and cultural characteristics, isolate GgPc22-1-11 was cultured on PDA and synthetic nutrient-poor agar (SNA) at 25°C under near-UV light with a 12-h photoperiod for 10 days. The colonies of GgPc22-1-11 on PDA were initially white and subsequently appeared light gray to olivaceous with white margins. The reverse side of the plates were dark brown and slate blue (Supplementary Fig. S1). Colonies on SNA were flat with an entire margin and short sparse white aerial mycelium. No setae were observed. Conidia on PDA were hyaline, straight, aseptate with a rounded apex, clavate to cylindrical, and measured 16.4 ± 2.4 (10.8-23.8) × 5.5 ± 0.7 (3.6-7.7) µm (n = 200). Appressoria were medium-to-dark brown, aseptate, solitary or in groups with irregular outlines, and lobate or having undulate margins (Supplementary Fig. S1). These morphological and cultural characteristics of GgPc22-1-11 were consistent with those of Colletotrichum grevilleae F. Liu, Damm, L. Cai & Crous, pathogens of Proteaceae and Punica granatum (Liu et al. 2013; Huang et al. 2023). DNA was extracted from GgPc22-1-11, PCR was performed and Phylogenetic analysis of concatenated partial sequences of the internal transcribed spacer (ITS) of rDNA, ß-tubulin (TUB2), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), chitin synthase 1 (CHS-1), and actin (ACT) genes was conducted (Weir et al. 2012). The resulting sequences were deposited in GenBank under the accession numbers LC773710-LC773714. A nucleotide BLAST search revealed that the ITS sequences of the isolates were 98.95% identical to those of C. grossum CAUG7 (KP890165.1). The TUB2, GAPDH, CHS-1, and ACT sequences of the isolates were 99.79%, 99.24%, 100%, and 100%, respectively, identical to those of C. grevilleae WP4. GgPc22-1-11 was clustered with C. grevilleae WP4 using neighbor joining analysis conducted with MEGA X software (Kumar et al. 2018) (Supplementary Fig. S2). Pathogenicity tests were conducted using GgPc22-1-11 and repeated three times. A total of 12 symptomless apples of each variety were selected, including Fuji, Hongro, Tsugaru, and RubyS. The apples were surface-sterilized with 70% ethanol and wounded using a sterile needle. Both wounded and unwounded apples were inoculated with mycelium plugs and paper disks containing a conidial suspension (1 × 106 conidia/ml) and placed in a plastic box with moist paper towels (>90% relative humidity) at 25°C in dark. At 5 days after inoculation, all artificially wounded fruits exhibited symptoms and 30% (4 out of 12) of unwounded inoculated fruits showed symptoms in each apple variety while control fruits were asymptomatic both the unwounded and wounded inoculations (Supplementary Fig. S1). To fulfill Koch's postulates, the fungi were reisolated from symptomatic tissues and were identical to GgPc22-1-11 confirmed by morphological and molecular analysis. To the best of our knowledge, C. grevilleae has been reported in Protea sp. and pomegranate (Liu et al. 2013; Huang et al. 2023) but not in apples to date, and this is the first report of C. grevilleae causing anthracnose in apple fruits. This research of the newly emerged unreported Colletotrichum species can offer valuable information for development of an effective fungicide spray program to control apple anthracnose.

2.
Curr Microbiol ; 80(9): 308, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37528256

RESUMO

A single Pectobacterium-like strain named 13-115T was isolated from a specimen of diseased cucumber stem tissue collected on Jeju Island, South Korea. The strain presented a rod-like shape and was negative for Gram staining. When grown on R2A medium at 25 °C, strain 13-115T formed round, convex and white colonies. This strain showed growth at temperatures ranging from 10 to 30 °C and tolerated a pH range of 6-9. The strain could also tolerate NaCl concentrations up to 5%. Analysis of the 16S rRNA gene sequence revealed that strain 13-115T exhibited similarity of over 99% with Pectobacterium brasiliense, P. carotovorum, P. polaris, and P. parvum. By conducting multilocus sequence analyses using dnaX, leuS, and recA genes, a separate phylogenetic lineage was discovered between strain 13-115T and other members of the genus Pectobacterium. Moreover, the strain showed relatively low in silico DNA-DNA hybridization (<60.6%) and average nucleotide identity (ANI) (<94.9%) values with recognized Pectobacterium species. The isolate has a genome size of 5,069,478 bp and a genomic G + C content of 52.04 mol%. Major fatty acids identified in the strain included C16:0 (28.99%), summed feature 3 (C16:1 ω7c and/or C16:1 ω6c; 28.85%), and C18:1 ω7c (19.01%). Pathogenicity assay confirmed that the novel strain induced soft rot symptoms in cucumber plants and Koch's postulates were fulfilled. Molecular analysis and phenotypic data indicated that strain 13-115T could be classified as a new species within the Pectobacterium genus, which has been named Pectobacterium jejuense. The type strain is 13-115T (= KCTC 92800T = JCM 35940T).


Assuntos
Cucumis sativus , Pectobacterium , Filogenia , RNA Ribossômico 16S/genética , Ácidos Graxos/química , Pectobacterium/genética , DNA , DNA Bacteriano/genética , DNA Bacteriano/química , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , Fosfolipídeos/química , Hibridização de Ácido Nucleico
3.
Plant Dis ; 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37261872

RESUMO

Oriental melon (Cucumis melo L.) is a popular Korean, Japanese, and Chinese fruit (Shin et al. 2017). In April 2022, abnormal fruit (n=20) that were collected in Sangju in Gyeongbuk Province (36°27'54.6"N, 128°10'49.7"E), Korea showed approximately 5% disease incidence with severity of 10-15%. Initial symptoms included shriveling, soaking, softening, dark discoloration, and sunken lesions. Internally, a rot extended to flesh, darkening from brown to black, and producing black mycelial masses. Two fungal strains (OM-rot-01 and OM-rot-02) were isolated and exhibited similar culture characteristics: aerial mycelium that was flat and pale grey to olivaceous on potato dextrose (PDA), malt extract (MEA), and oatmeal agar (OA) after seven days at 25°C and produced abundant buff-colored pycnidial ascomata on OA. Asci were bitunicate, clavate to cylindrical, 48.4 to 69.0 × 6.1 to 6.9 µm (n=10), and ascospores were biseriate, sparse, ellipsoidal, straight to slightly curved, hyaline, smooth, apex obtuse, 1-septate, 11.1 to 14.9 × 3.8 to 5.4 µm (n=20). Conidiomata were pycnidial, mostly solitary, irregular, pale brown to black, semi-immersed, 150 to 220 × 120 to 200 µm. Conidia were oblong or ovoid, smooth, thin-walled, hyaline, aseptate, 4.4 to 6.7 × 2.0 to 2.8 µm (n=35), with 1-3 guttules per conidium. The morphological characteristics corresponded to those of Stagonosporopsis cucumeris (Hou et al. 2020). For molecular identification, genomic DNA was extracted from strains (OM-rot-01 and OM-rot-02), and the ITS regions, partial 28S rDNA (LSU), beta-tubulin (TUB2), and RNA polymerase II second largest subunit (RPB2) genes were amplified and sequenced (White et al. 1990; Woudenberg et al. 2009; Vilgalys & Hester 1990; Liu et al. 1999). The obtained sequences revealed 99-100% homology with S. cucumeris accessions (MH858625, MH870265, MT005554, and MT018021). The sequences were deposited in GenBank with accession nos. for ITS regions (OP788058, OP788059), 28S rDNA (OP788094, OP788095), TUB2 (OP810568, OP810569), and RPB2 (OP810570, OP810571). Phylogenetic analysis combined with ITS, LSU, TUB2, and RPB2 concatenated sequences using neighbor-joining method revealed that the strains were S. cucumeris. To confirm pathogenicity, OM-rot-01 was inoculated onto ripe, asymptomatic Oriental melon fruit (n=6). After they were surface sterilized with 70% alcohol, fruit were wounded using a sterilized needle and corkborer, and 5-mm-diameter mycelial plugs were attached to the wound sites, followed by covering of the fruit with aluminum foil and maintenance in a plastic box (>90% relative humidity) at 25°C. Non-wounded fruit were inoculated and incubated in a similar manner, and fruit that were inoculated with PDA plugs served as controls (n=3). The aluminum foil was removed after three days of inoculation, and other conditions were kept constant. After six days, typical internal fruit rot symptoms were observed in both wounded and non-wounded fruit; brown to black rot extended into flesh, whereas control fruit remained asymptomatic. Fungi reisolated from lesions were morphologically identical to OM-rot-01; identity was confirmed by molecular analysis, fulfilling Koch's postulates, and the pathogenicity test was conducted three times. S. cucumeris was found as a canker on Cucumis sativus in the Netherlands (Hou et al. 2020), but has not been reported elsewhere as a pathogen on Cucumis spp. To our knowledge, this is the first report of S. cucumeris causing internal fruit rot on Oriental melon in Korea. This disease poses a threat to melon production, so accurate identification of the pathogen is a key starting point for development of sustainable management practices.

4.
Arch Insect Biochem Physiol ; 111(4): e21965, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36053552

RESUMO

The fall armyworm (FAW) Spodoptera frugiperda is an important invasive pest in Africa and Asia. It is a polyphagous pest with at least 353 recorded host plant species, including corn. Chemical control of this pest is unsuccessful because of a developed resistance and harmful effects on the environment. Entomopathogenic fungi are potential biological control agents for FAW. In this study, the native strain of Metarhizium rileyi (KNU-Ye-1), collected from a cornfield at Yeongcheon, Korea, was identified by morphological and molecular characterization. The susceptibility of the fourth-instar larvae of FAW to the native strain M. rileyi was examined in the laboratory. The results showed that the Korean strain of M. rileyi (KNU-Ye-1) was highly virulent to FAW larvae, causing 89% mortality 7 days posttreatment. Therefore, M. rileyi (KNU-Ye-1) identified in this study is highly valuable for the biological control of FAW in the field.


Assuntos
Metarhizium , Animais , Spodoptera/microbiologia , Virulência , Larva
5.
Curr Microbiol ; 79(2): 71, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35059849

RESUMO

A Gram-negative, motile by gliding, rod-shaped, aerobic bacterium, designated SD-bT, was isolated from a soil sample collected on Dokdo Island, South Korea. A polyphasic approach based on phenotypic, phylogenetic, and genomic analyses was used to characterize the new isolate. Phylogenetic analysis of 16S rRNA gene sequence showed that strain SD-bT belonged to the family Sphingobacteriaceae and most closely related to Pedobacter psychrophilus P4487AT (95.9% similarity). The isolate contained MK-7 as the predominant respiratory quinone; its main polar lipid was phosphatidylethanolamine; and the major fatty acids were summed feature 3 (C16:1 ω7c/C16:1 ω6c; 32.0%), C15:0 iso (19.1%), C17:0 iso 3-OH (8.3%), and C16:0 (8.2%). The draft genome had a length of 3,842,102 bp with a G+C content of 36.0 mol%, predicting 3282 coding sequences, 3 rRNA genes, 3 ncRNAs, and 36 tRNAs genes. The digital DNA-DNA hybridization and average nucleotide identity values between strain SD-bT and P. psychrophilus LMG 29436T were 22.0% and 78.9%, respectively. The results of phenotypic properties, genotypic distinctiveness, and chemotaxonomic features support the discrimination of SD-bT from its phylogenetic relatives. Pedobacter segetis sp. nov. is therefore proposed with SD-bT (= KCTC 82351T = JCM 34283T) as the type strain.


Assuntos
Pedobacter , DNA Bacteriano/genética , Pedobacter/genética , Filogenia , RNA Ribossômico 16S/genética , Solo , Microbiologia do Solo
6.
Proc Natl Acad Sci U S A ; 116(52): 26394-26401, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31843926

RESUMO

The flux of solutes from the chemical weathering of the continental crust supplies a steady supply of essential nutrients necessary for the maintenance of Earth's biosphere. Promotion of weathering by microorganisms is a well-documented phenomenon and is most often attributed to heterotrophic microbial metabolism for the purposes of nutrient acquisition. Here, we demonstrate the role of chemolithotrophic ferrous iron [Fe(II)]-oxidizing bacteria in biogeochemical weathering of subsurface Fe(II)-silicate minerals at the Luquillo Critical Zone Observatory in Puerto Rico. Under chemolithotrophic growth conditions, mineral-derived Fe(II) in the Rio Blanco Quartz Diorite served as the primary energy source for microbial growth. An enrichment in homologs to gene clusters involved in extracellular electron transfer was associated with dramatically accelerated rates of mineral oxidation and adenosine triphosphate generation relative to sterile diorite suspensions. Transmission electron microscopy and energy-dispersive spectroscopy revealed the accumulation of nanoparticulate Fe-oxyhydroxides on mineral surfaces only under biotic conditions. Microbially oxidized quartz diorite showed greater susceptibility to proton-promoted dissolution, which has important implications for weathering reactions in situ. Collectively, our results suggest that chemolithotrophic Fe(II)-oxidizing bacteria are likely contributors in the transformation of rock to regolith.

7.
Medicina (Kaunas) ; 58(8)2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-36013552

RESUMO

Introduction: Adequate bone quality is essential for long term biologic fixation of cementless total knee arthroplasty (TKA). Recently, vertebral bone quality evaluation using dual-energy computed tomography (DECT) has been introduced. However, the DECT bone mineral density (BMD) in peripheral skeleton has not been correlated with Hounsfield units (HU) or central dual-energy X-ray absorptiometry (DXA), and the accuracy remains unclear. Materials and methods: Medical records of 117 patients who underwent TKA were reviewed. DXA was completed within three months before surgery. DECT was performed with third-generation dual source CT in dual-energy mode. Correlations between DXA, DECT BMD and HU for central and periarticular regions were analyzed. Receiver operating characteristic (ROC) curves were plotted and area under the curve (AUC), optimal threshold, and sensitivity and specificity of each region of interest (ROI) were calculated. Results: Central DXA BMD was correlated with DECT BMD and HU in ROIs both centrally and around the knee (all p < 0.01). The diagnostic accuracy of DECT BMD was higher than that of DECT HU and was also higher when the T-score for second lumbar vertebra (L2), rather than for the femur neck, was used as the reference standard (all AUC values: L2 > femur neck; DECT BMD > DECT HU, respectively). Using the DXA T-score at L2 as the reference standard, the optimal DECT BMD cut-off values for osteoporosis were 89.2 mg/cm3 in the distal femur and 78.3 mg/cm3 in the proximal tibia. Conclusion: Opportunistic volumetric BMD assessment using DECT is accurate and relatively simple, and does not require extra equipment. DECT BMD and HU are useful for osteoporosis screening before cementless TKA.


Assuntos
Densidade Óssea , Osteoporose , Absorciometria de Fóton/métodos , Colo do Fêmur , Humanos , Vértebras Lombares , Osteoporose/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
8.
Arch Microbiol ; 203(7): 4201-4208, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34085113

RESUMO

A Gram-stain negative, rod shaped, motile by gliding, yellow-pigmented, aerobic bacterium, designated SE-1-eT, was isolated from a soil sample collected on Dokdo Island, South Korea. The isolate was characterized taxonomically using a polyphasic approach based on the phenotypic and genomic analyses. The phylogenetic analysis based on 16S rRNA gene sequence revealed that strain SE-1-eT belonged to the genus Flavobacterium in the family Flavobacteriaceae and had the highest sequence similarity with Flavobacterium cheongpyeongense IMCC34759T (97.5%), Flavobacterium arsenitoxidans S2-3HT (97.4%), Flavobacterium resistens BD-b365T (97.4%), and Flavobacterium chungangense CJ7T (97.4%). The predominant respiratory quinone of the isolate was found to be MK-6; the main polar lipid was phosphatidylethanolamine; and the major fatty acids were identified as summed feature 3 (C16:1 ω7c/C16:1 ω6c), C15:0 iso, and C16:0. The draft genome of strain SE-1-eT had a length of 3,715,609 bp and a DNA G + C content of 34.8 mol%. The nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between the novel isolate and F. cheongpyeongense IMCC34759T, F. resistens BD-b365T, and Flavobacterium chungangense CJ7T ranged from 74.9 to 75.3% and from 20.2 to 20.9%, respectively. On the basis of its phenotypic properties, genotypic distinctiveness, and chemotaxonomic features, strain SE-1-eT represents a novel species in the genus Flavobacterium, for which the name Flavobacterium agrisoli sp. nov. is proposed. The type strain is SE-1-eT (= KCTC 82352 T = JCM 34302 T).


Assuntos
Flavobacterium , Microbiologia do Solo , Ácidos Graxos/análise , Flavobacterium/classificação , Flavobacterium/genética , Filogenia , RNA Ribossômico 16S/genética , República da Coreia , Especificidade da Espécie
9.
Appl Opt ; 60(4): A54-A61, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33690354

RESUMO

In a digital hologram, the maximum viewing angle of a computer-generated hologram (CGH) is limited by pixel pitch due to the diffraction grating equation. Since reducing pixel size of display panel is challenging and costly, we propose a method to expand the viewing angle of a digital hologram by attaching an aligned pixelated random phase mask (PRPM) onto the CGH pattern based on analysis of simulation results. By introducing a phase-averaging process to the widely used iterative Fourier transform algorithm, an optimized CGH pattern can be obtained in conjunction with a PRPM. Based on scalar diffraction theory, viewing angle enhancement characteristics were verified by comparing the perspective views of a two-plane hologram using a virtual eye model. In addition, we performed full electromagnetic simulations that included effects due to potential fabrication errors such as misalignment, thickness variation, and internal reflections and diffractions between the CGH and random mask patterns. From the simulation results, by attaching a 1.85 µm-sized pixel pitch PRPM to a 3.7 µm CGH, the viewing angle can be easily expanded almost identical to that of a CGH with 1.85 µm-pixel pitch.

10.
Curr Microbiol ; 78(8): 3328-3333, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34173841

RESUMO

A bacterial strain, designated BT258T, was isolated from a soil sample collected from Uijeongbu-si, Gyeong-do Province, Republic of Korea. Cells were Gram stain negative, aerobic, rod shaped, motile by gliding, and formed light pink-pigmented colonies on agar plates. Growth of the isolate was observed at 10-37 °C and pH 6-7. A 16S rRNA gene sequence analysis revealed that strain BT258T is a member of the genus Adhaeribacter in the family Hymenobacteraceae and had the highest sequence similarity with 'Adhaeribacter soli' MA2T (97.1%), Adhaeribacter terreus DNG6T (96.6%), and Adhaeribacter terrae HY02T (96.5%). The predominant respiratory quinone of the isolate was MK-7, the main polar lipid was phosphatidylethanolamine, and the major fatty acids were C15:0 iso (37.7%), summed feature 4 (C17:1 anteiso B/iso-C17:1 I; 16.8%), and C16:0 (10.3%). The draft genome of strain BT258T had a whole length of 4,974,022 bp and DNA G + C content of 46.0 mol%. The digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values between the novel isolate and 'Adhaeribacter soli' and seven other Adhaeribacter species ranged from 17.9 to 22.7% and 69.7 to 77.9%, respectively. On the basis of its phenotypic properties, genotypic distinctiveness, and chemotaxonomic features, strain BT258T represents a novel species in the genus Adhaeribacter, for which the name Adhaeribacter terrigena sp. nov. is proposed. The type strain is BT258T (= KCTC 72409 T = JCM 34303 T).


Assuntos
Microbiologia do Solo , Solo , Técnicas de Tipagem Bacteriana , Bacteroidetes , DNA Bacteriano/genética , Ácidos Graxos/análise , Filogenia , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA
11.
Curr Microbiol ; 78(6): 2447-2454, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33909088

RESUMO

A bacterial strain, SD-gT, was isolated from a soil sample collected on Dokdo Island, South Korea. Cells were observed to be Gram stain negative and short rod shaped, and colonies to be pink in color. Growth of the isolate was observed at 4-30 °C, pH 6-8, and in the presence of 0-2.0% NaCl. Analysis of 16S rRNA gene sequences identified strain SD-gT as a member of the genus Mucilaginibacter in the family Sphingobacteriaceae, with high levels of sequence similarity with Mucilaginibacter terrenus ZH6T (96.9%), Mucilaginibacter lutimaris BR-3T (96.8%), Mucilaginibacter carri PR0008KT (96.8%), Mucilaginibacter gilvus F01003T (96.7%), Mucilaginibacter litoreus BR-18T (96.6%), and Mucilaginibacter terrigena 17JY9-4T (96.5%). The genomic DNA G+C content of strain SD-gT was calculated to be 40.6 mol%. The predominant respiratory quinone of the isolate was found to be MK-7; the main polar lipid was phosphatidylethanolamine; and the major fatty acids were identified as summed feature 3 (C16:1 ω7c/C16:1 ω6c; 29.0%), C15:0 iso (19.1%), C15:0 iso (28.1%), C16:0 (14.9%), and C17:0 iso 3-OH (7.4%). The digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values between strain SD-gT and M. terrenus ZH6T, M. gilvus F01003T, and M. terrigena ranged from 17.7 to 18.4% and 72.1 to 74.0%, respectively. On the basis of its phenotypic properties, genotypic distinctiveness, and chemotaxonomic features, strain SD-gT represents a novel species in the genus Mucilaginibacter, for which the name Mucilaginibacter segetis sp. nov. is proposed. The type strain is SD-gT (= KCTC 82353T = JCM 34284T).


Assuntos
Microbiologia do Solo , Solo , Técnicas de Tipagem Bacteriana , Bacteroidetes , DNA Bacteriano/genética , Ácidos Graxos/análise , Filogenia , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA
12.
Sensors (Basel) ; 21(12)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198657

RESUMO

Diffraction is a fundamental phenomenon that reveals the wave nature of light. When a plane wave is transmitted or reflected from a grating or other periodic structures, diffracted light waves propagate at several angles that are specified by the period of the given structure. When the optical period is shorter than the wavelength, constructive interference of diffracted light rays from the subwavelength-scale grating forms a uniform plane wave. Many studies have shown that through the appropriate design of meta-atom geometry, metasurfaces can be used to control light properties. However, most semitransparent metasurfaces are designed to perform symmetric operation with regard to diffraction, meaning that light diffraction occurs identically for front- and back-side illumination. We propose a simple single-layer plasmonic metasurface that achieves asymmetric diffraction by optimizing the transmission phase from two types of nanoslits with I- and T-shaped structures. As the proposed structure is designed to have a different effective period for each observation side, it is either diffractive or nondiffractive depending on the direction of observation. The designed structure exhibits a diffraction angle of 54°, which can be further tuned by applying different period conditions. We expect the proposed asymmetric diffraction meta-grating to have great potential for the miniaturized optical diffraction control systems in the infrared band and compact optical diffraction filters for integrated optics.

13.
Arch Microbiol ; 202(3): 637-643, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31776587

RESUMO

A bacterial strain isolated from a soil collected in Jeju Island, designated as 17J7-1T, was Gram-negative, rod-shaped, yellow colored, and motile by gliding. This strain was able to grow at temperature range from 10 to 42 °C, pH 7-9, and tolerated up to 1% NaCl. Analysis of 16S rRNA sequence identified strain 17J7-1T as a member of the genus Lysobacter with close sequence similarity with Lysobacter mobilis 9NM-14T (97.4%), Lysobacter xinjiangensis RCML-52T (97.0%), and Lysobacter humi FJY8T (96.9%). The genomic DNA G + C content of the isolate was 67.9 mol%. DNA-DNA relatedness between strain 17J7-1T and L. mobilis, L. humi, and L. xinjiangensis were 42.3%, 39.5%, and 35.8%, respectively, clearly showing that the isolate is distinct from its closest phylogenetic neighbors in the genus Lysobacter. Average nucleotide identity (ANI) and digital DNA-DNAhybridization (dDDH) values between strain 17J7-1T and L. enzymogenes ATCC 29487T, the type species of this genus, and several other close Lysobacter species were less than 77% and 22%, respectively. Major fatty acids were C16:0 iso (29.8%), summed feature 9 (C17:1 iso ω9c/C16:0 10-methyl; 20.1%), and C15:0 iso (17.7%). The predominant respiratory quinone was ubiquinone Q-8 and the major polar lipids were phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol. In the light of the polyphasic evidence accumulated in this study, strain 17J7-1T is considered to represent a novel species in the genus Lysobacter, for which name Lysobacter terrigena sp. nov. is proposed. The type strain is 17J7-1T (= KCTC 62217T = JCM 33057T).


Assuntos
Lysobacter/isolamento & purificação , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Lysobacter/classificação , Lysobacter/genética , Lysobacter/metabolismo , Fosfolipídeos/análise , Fosfolipídeos/metabolismo , Filogenia , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA
14.
Arch Microbiol ; 202(4): 747-754, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31796988

RESUMO

A bacterial strain, 17J42-1T, was isolated from a soil sample collected on Jeju Island, Republic of Korea. Colonies grown on R2A agar were pink in color, and cells were Gram-stain negative, short and rod-shaped. Analysis of 16S rRNA gene sequences identified this strain as a member of the genus Methylobacterium in the family Methylobacteriaceae, with high levels of 16S rRNA sequence similarity shared with Methylobacterium oxalidis 35aT (98.6%), Methylobacterium jeotgali S2R03-9T (97.5%), and Methylobacterium soli YIM 48816T (97.3%). Cells grew at 15-35 °C, pH 5-9, and in the presence of 0-1.0% NaCl. The genomic G + C content was 70.2 mol% based on the whole genome analysis. The predominant respiratory quinone was ubiquinone Q-10, the major fatty acid was C18:1ω7c (85.3%), and the major polar lipids were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, and diphosphatidylglycerol. The phenotypic and chemotaxonomic data support the affiliation of strain 17J42-1T with the genus Methylobacterium. However, the DNA-DNA relatedness between the isolate and its closest phylogenetic neighbors was lower than 38%. The OrthoANI and dDDH values between strain 17J42-1T and the closest type strain Methylobacterium oxalidis NBRC 107715T were calculated to be 85.9% and 30.6%, respectively. The results of 16S rRNA gene sequence similarity analysis, DNA-DNA hybridization analysis, and the observed differentiating phenotypic properties from other closely related taxa clearly indicate that strain 17J42-1T represents a novel species in the genus Methylobacterium, for which the name Methylobacterium segetis sp. nov. is proposed. The type strain is 17J42-1T (= KCTC 62267T = JCM 33059T).


Assuntos
Methylobacterium/classificação , Microbiologia do Solo , Composição de Bases , Ácidos Graxos/química , Methylobacterium/genética , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Especificidade da Espécie
15.
Mol Biol Rep ; 47(11): 8429-8438, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33037963

RESUMO

Plant-rhizobacteria interaction and co-evolution developed adaptive strategies which may help the plant survive in nature. Plant rhizosphere soil isolates were analyzed to investigated the effects of rhizobacteria for promoting plant growth and suppress plant disease. Bacterial strains which isolated from plant rhizosphere soil were screened for elicitation of induced systemic resistance (ISR) on tobacco. Strain S2-3-2 results in significant reduction of disease severity on tobacco, it was identified as Bacillus pumilus by multilocus sequence analysis (MLSA). Strain S2-3-2 was deeper studied for pepper plant growth promotion and biological control activity against pepper bacterial spot disease. It was found that the pepper disease severity was decreased when the roots were drenched with strain S2-3-2, and the pepper plants had a higher weight and chlorophyll content, as compared with the mock-treated plants. Transcriptional expression of pathogenesis-related (PR) protein genes in pepper was analyzed by real-time PCR, gene expressions of CaPR1, CaPR4, and CaPR10 were increased when the plants were treated with strain S2-3-2. Moreover, strain S2-3-2 was tested for the production of indole-3-acetic acid (IAA), and it was determined to emit volatiles that enhance the growth of the tobacco plants. Interesting, heat-killed S2-3-2 enhance the pepper root growth, increase the gene expressions of CaPR4 and CaPR10 after pathogen challenge for 6 h, but limited to suppress the pepper bacterial spot disease as compare to the mock-treated plants. Strain S2-3-2 can be a potential biological control agent on the plant root for plant growth promoting and disease suppression.


Assuntos
Bacillus pumilus/isolamento & purificação , Raízes de Plantas/crescimento & desenvolvimento , Rizosfera , Microbiologia do Solo , Bacillus pumilus/genética , Bacillus pumilus/fisiologia , Capsicum/genética , Capsicum/crescimento & desenvolvimento , Capsicum/microbiologia , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Tipagem de Sequências Multilocus/métodos , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/microbiologia , Nicotiana/genética , Nicotiana/crescimento & desenvolvimento , Nicotiana/microbiologia
16.
Curr Microbiol ; 77(1): 166-172, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31728699

RESUMO

A Gram-negative, aerobic, motile by gliding, rod-shaped bacterium, strain 17J68-2T, was isolated from a soil sample taken from Jeju Island, Republic of Korea. The isolate displayed high 16S rRNA gene sequence similarity to the members of the genus Lysobacter in the family Lysobacteraceae, with Lysobacter humi FJY8T (98.4% similarity), Lysobacter xinjiangensis RCML-52T (98.3%), and Lysobacter mobilis 9NM-14T (98.1%) as closest phylogenetic neighbors. Growth of strain 17J68-2T occurred at 15-42 °C, pH 7-8, and in the presence of 0-1.0% NaCl. Draft genome was 2.94 Mb in size with G+C content of 70.5 mol%. The major polar lipids were phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylethanolamine. Ubiquinone Q-8 was the predominant respiratory quinone and the major fatty acids were C16:0 iso (39.4%), summed feature 3 (C16:1ω7c/C16:1ω6c) (6.6%), C11:0 iso 3-OH (6.4%), C15:0 iso (6.4%), and C16:1 iso H (6.2%). The DNA-DNA relatedness between strain 17J68-2T and L. humi, L. xinjiangensis, and L. mobilis were 39.9, 39.4, and 25.3%, respectively. From these results, it is concluded that the novel isolate possesses sufficient characteristics to differentiate it from the most closely affiliated Lysobacter species, and strain 17J68-2T represents a novel species of the genus Lysobacter, for which the name Lysobacter segetis sp. nov. (=KCTC 62237T = JCM 33058T) is proposed.


Assuntos
Lysobacter/genética , Técnicas de Tipagem Bacteriana , Composição de Bases/genética , DNA Bacteriano/genética , Lysobacter/classificação , Lysobacter/metabolismo , Filogenia , RNA Ribossômico 16S/genética , Microbiologia do Solo
17.
Sensors (Basel) ; 20(21)2020 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-33171796

RESUMO

This study presents a computational method called economical auto moment limiter (eAML) that prevents a mobile cargo crane from being overloaded. The eAML detects and controls, in real time, crane overload without using boom stroke sensors and load cells, which are expensive items inevitable to existing AML systems, hence, being competitive in price. It replaces these stroke sensors and load cells that are used for the crane overload measurement with a set of mathematical formula and control logics that calculates the lifting load being handled under crane operation and the maximum lifting load. By calculating iterative them using only a pressure sensor attached under the derrick cylinder and the boom angle sensor, the mathematical model identifies the maximum descendible angle of the boom. The control logic presents the control method for preventing the crane overload by using the descendible angle obtained by the mathematical model. Both the mathematical model and the control logic are validated by rigorous simulation experiments using MATLAB on two case instances each of which eAML is used and not used, while changing the pressures on the derrick cylinder and the boom angle. The effectiveness and validity of the method are confirmed by comparing the outputs obtained by the controlled experiments performed by using a 7.6 ton crane on top of SCS887 and a straight-type maritime heavy-duty crane along with eAML. The effects attributed to the load and the wind speed are quantified to verify the reliability of eAML under the changes in external variables.

18.
Opt Express ; 27(14): 19119-19129, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31503675

RESUMO

A metasurface is a planar optical device that controls the phase, amplitude, and polarization of light through subwavelength-scale unit elements, called meta-atom. The tunability of plasmonic vortex lens (PVL) which generates surface plasmon polaritons (SPPs) carrying orbital angular momentum can be improved by using meta-atom. However, conventional PVLs exhibit nonuniform field profiles according to the incident polarization states owing to the spin-orbital interaction (SOI) effect observed during SPP excitation. This paper describes a method of compensating for SOI of PVL by using the geometric phase of distributed nanoslits in a gold film. By designing the orientation angles of slit pairs, the anti-phase of the SOI effect can be generated for compensatory effect. In addition, polarization-independent PVLs are designed by applying a detour phase based on the position of the slit pairs. PVLs for center-, off-center-, and multiple-focus cases are demonstrated and measured via a near-field scanning microscope.

19.
Biometals ; 32(5): 803-811, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31549273

RESUMO

Sulfate-reducing bacteria have been suggested to have an etiological role in the development of inflammatory bowel diseases and ulcerative colitis in humans. Traditionally. bismuth compounds have been administered to alleviate gastrointestinal discomfort and disease symptoms. One mechanism by which this treatment occurs is through binding bacterial derived hydrogen sulfide in the intestines. With the addition of bismuth-deferiprone, bismuth-citrate and bismuth subsalicylate to reactions containing cells of D. desulfuricans ATCC 27774, the oxidation of H2 with sulfate as the electron acceptor was inhibited but H2 oxidation with nitrate, nitrite and sulfite was not reduced. Our research suggests that a target for bismuth inhibition of D. desulfuricans is the F1 subunit of the ATP synthase and, thus, dissimilatory sulfate reduction does not occur. At sublethal concentrations, bismuth as Bi(III) is precipitated by hydrogen sulfide produced from respiratory sulfate reduction by D. desulfuricans. Nanocrystals of bismuth sulfide were determined to be Bi2S3 through the use of high resolution transmission electron microscopy imaging with X-ray energy-dispersive spectroscopy analysis. In the absence of sulfate, D. desulfuricans oxidizes H2 with the reduction of Bi(III) to Bi0 and this was also established by X-ray energy-dispersive spectroscopy analysis.


Assuntos
Bismuto/química , Nanopartículas/química , Adenosina Trifosfatases/metabolismo , Anaerobiose , Bismuto/farmacologia , Desulfovibrio desulfuricans/efeitos dos fármacos , Testes de Sensibilidade Microbiana
20.
Curr Microbiol ; 76(1): 117-123, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30446787

RESUMO

A Gram-stain-negative, non-motile, rod-shaped bacterial strain, designated 9-2-1-1T, was isolated from apple orchard soil in Daegu, Republic of Korea. Comparative 16S rRNA gene sequence analysis showed that the isolate belongs to the family Cytophagaceae, Bacteroidetes and it is most closely related to Hymenobacter metalli A2-91T (97.8% similarity) and Hymenobacter marinus KJ035T (96.6%). Growth of strain 9-2-1-1T was observed at 4-30 °C, pH 6-8, and in the presence of 0-1.0% NaCl. The G+C content of the genomic DNA was 62.0 mol%. The predominant respiratory quinone of the isolate was MK-7; the major fatty acids were C15:0 iso (29.3%), C16:1ω5c (15.4%), C15:0 anteiso (12.5%), summed feature 3 (C16:1ω7c/C16:1ω6c; 12.3%), and C16:0 (10.6%); and the major polar lipid was phosphatidylethanolamine. The phenotypic and chemotaxonomic data supported the affiliation of strain 9-2-1-1T with the genus Hymenobacter. However, the DNA-DNA relatedness between the isolate and H. metalli and H. marinus were 31.3% and 24.7%, respectively. The DNA-DNA hybridization result and the differentiating phenotypic properties clearly indicate that strain 9-2-1-1T is the representative of a novel species in the genus Hymenobacter, for which the name Hymenobacter pomorum sp. nov. is proposed. The type strain is 9-2-1-1T (=KCTC 52740T = JCM 32193T).


Assuntos
Bacteroidetes/classificação , Bacteroidetes/isolamento & purificação , Malus/microbiologia , Microbiologia do Solo , Bacteroidetes/genética , Composição de Bases/genética , DNA Bacteriano/genética , Ácidos Graxos/análise , RNA Ribossômico 16S/genética , República da Coreia
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