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Rapid and efficient detection of pathogenic bacteria from food is critical to prevent epidemic food poisoning. However, the isolation of pathogenic bacteria from spoiled food is hampered by the lack of proper cell cultivation and/or isolation methods. Most of currently used methods suffer from complex, time-consuming culturing steps, low scalability, and high operation cost. Herein, we developed an alternative approach for the isolation of pathogenic bacteria directly from food using a surface-modified, highly porous sponge via initiated chemical vapor deposition (iCVD) process. A hydrophobic polymer, poly(2,4,6,8-tetravinyl-2,4,6,8-tetramethyl cyclotetra-siloxane) (pV4D4), was deposited conformally on amphiphilic 3-dimensional (3D) melamine sponge to incorporate hydrophobicity as well as oleophilicity to the porous sponge surface, which is appropriate for absorbing oil component selectively from food extracts. Furthermore, the surface-modified sponge was capable of the isolation of Escherichia coli O157:H7 (E. coli O157:H7) from heterogeneous mixture with oil/water/food particles with undistinguisible efficiency compare to artificial model system. The surface-modified sponge developed in this study will be a novel platform for oil/water separation and isolation of foodborne pathogens directly from heterogeneous mixture to enhance the efficiency of molecular diagnostics.

Rhodococcus fascians is an important pathogen that infects various herbaceous perennials and reduces their economic value. In this study, we examined R. fascians isolates carrying a virulence gene from symptomatic lily plants grown in South Korea. Phylogenetic analysis using the nucleotide sequences of 16S rRNA, vicA, and fasD led to the classification of the isolates into four different strains of R. fascians. Inoculation of Nicotiana benthamiana with these isolates slowed root growth and resulted in symptoms of leafy gall. These findings elucidate the diversification of domestic pathogenic R. fascians and may lead to an accurate causal diagnosis to help reduce economic losses in the bulb market.

Ginseng (Panax ginseng C.A. Meyer) is a medicinal crop that requires a long culture time before it is ready to harvest, thus generating high economic and environmental costs. Symbiotic bacteria that live within the plant provide the host plant with many advantages in terms of metabolism and disease resistance. Here, we isolated endophytic bacteria from various tissues of P. ginseng seedlings using a culture-dependent method and we compared their tissue distribution. In addition, their antimicrobial activity against two fungal pathogens was investigated. Based on 16S rRNA sequencing, we identified 21 bacterial strains from ginseng seedlings. Leaves and rhizomes showed higher bacterial species diversity than root bodies and tails. While Bacillus strains were detected in all tissues, Xanthomonas and Micrococcaceae strains were specifically isolated from rhizome and leaf tissues, respectively. Fourteen bacterial strains showed antimicrobial activities against Cylindrocarpon destructans and/or Botrytis cinerea, with different activities. Among them, two strains (PgKB29 and PgKB35) showed strong antimicrobial activities against both fungi. Taken together, these results provide a better understanding of endophytic bacteria in P. ginseng seedlings and suggest the possibility of biological control of fungal pathogens using endophytic bacteria.

// Sung Hee Jo 1, 2, 4, * , Ji-Ae Choi 1, 2, 4, * , Yun-Ji Lim 1, 2, 4 , Junghwan Lee 1, 2, 4 , Soo-Na Cho 1, 2, 4 , Sung-Man Oh 1, 2, 4 , Dam Go 1, 2, 4 , Seon-Hwa Kim 1, 2, 4 and Chang-Hwa Song 1, 2, 3, 4 1 Department of Medical Science, Chungnam National University, Daejeon, Republic of Korea 2 Department of Microbiology, Chungnam National University, Daejeon, Republic of Korea 3 Research Institute for Medical Sciences, Chungnam National University, Daejeon, Republic of Korea 4 College of Medicine, Chungnam National University, Daejeon, Republic of Korea * These authors have contributed equally to this work Correspondence to: Chang-Hwa Song, email: songch@cnu.ac.kr Keywords: ER stress, apoptosis, mycobacteria, calreticulin, macrophages Received: February 08, 2017 Accepted: March 28, 2017 Published: April 25, 2017 ABSTRACT Endoplasmic reticulum (ER)-stress-mediated apoptosis is a host defense mechanism against Mycobacterium tuberculosis (Mtb) infection. Calreticulin (CRT) is the major calcium-binding chaperone protein. Previous reports have suggested a close relationship between the cell-surface expression of CRT and apoptosis. In this study, the role of CRT during Mtb infection was examined. The results showed that Mtb infection induces CRT production by macrophages and that CRT levels are correlated with the degree of apoptotic cell death. The enhanced production of CRT was associated with the ER stress induced by Mtb infection. A significant increase in CRT translocation from the cytosol to the plasma membrane after 24 h of infection suggested the importance of CRT localization in the induction of apoptosis during Mtb infection. An investigation of the factors associated with CRT translocation and the ability of ectopically expressed CRT to induce apoptosis showed that pretreatment with a reactive oxygen species scavenger decreased Mtb-induced CRT expression, leading to the reduction of CHOP and caspase-3 activation. The intracellular survival of Mtb was significantly higher in macrophages transfected with a CRT-specific small interfering RNA than in control cells. The key role of CRT in inducing apoptosis included its interaction with CXCR1 and TNFR1 in Mtb-infected macrophages. The CRT/CXCR1/TNFR1 complex was shown to induce the extrinsic apoptotic pathway during Mtb infection. Together, these results demonstrate that CRT is critical for the intracellular survival of Mtb, via ER-stress-induced apoptosis, as well as the importance of ER stress-mediated CRT localization in the pathogenesis of tuberculosis.

Shigella, which infects primates, can be transmitted via fresh vegetables; however, its molecular interactions with plants have not been elucidated. Here, we show that four Shigella strains, Shigella boydii, Shigella sonnei, Shigella flexneri 2a, and S. flexneri 5a, proliferate at different levels in Arabidopsis thaliana. Microscopic studies revealed that these bacteria were present inside leaves and damaged plant cells. Green fluorescent protein (GFP)-tagged S. boydii and S. flexneri 5a colonized leaves only, whereas S. flexneri 2a colonized both leaves and roots. Using Shigella mutants lacking type III secretion systems (T3SSs), we found that T3SSs that regulate the pathogenesis of shigellosis in humans also play a central role in bacterial proliferation in Arabidopsis. Strikingly, the immunosuppressive activity of two T3S effectors, OspF and OspG, was required for proliferation of Shigella in Arabidopsis. Of note, delivery of OspF or OspG effectors inside plant cells upon Shigella inoculation was confirmed using a split GFP system. These findings demonstrate that the human pathogen Shigella can proliferate in plants by adapting immunosuppressive machinery used in the original host human.

Rhodococcus species have become increasingly important owing to their ability to degrade a wide range of toxic chemicals and produce bioactive compounds. Here, we report isolation of the Rhodococcus sp. KB6, which is a new leaf-inhabiting endophytic bacterium that suppresses black rot disease in sweet potato leaves. We determined the 7.0 Mb draft genome sequence of KB6 and have predicted 19 biosynthetic gene clusters for secondary metabolites, including heterobactins, which are a new class of siderophores. Notably, we showed the first internal colonization of host plants with Rhodococcus sp. KB6 and discuss its potential as a biocontrol agent for sustainable agriculture.

Human enteropathogenic bacteria has been reported to be transmitted by fresh vegitables.Shigella, which infects primates, is reportedly transmitted by fresh vegetables; however, its molecular interactions with plants have not been elucidated. Here, we show that fourShigellastrains,S. boydii(S. b),S. sonnei,S. flexneri2a (S. f2a), andS. flexneri5a (S. f5a), proliferated at different levels inArabidopsis thaliana. Microscopic studies revealed that these bacteria were present inside leaves and damaged plant cells. Green fluorescent protein (GFP)-taggedS. bandS. f5a colonized in leaves only, andS. f2a colonized both leaves and roots. Using mutants lacking type III secretion systems (T3SS), we found that T3SS ofShigellathat regulate the pathogenesis of Shigellosis in humans also play a central role in proliferation inArabidopsis.Strikingly, the immunosuppressive activity of two T3S effectors, OspF and OspG, were needed for the proliferation ofShigellainArabidopsis. Of note, delivery of OspF or OspG effectors inside of plant cells uponShigellainoculation was confirmed by using a split GFP system, respectively. These findings demonstrate that the human pathogenShigellacan proliferate in plants by adoption of immunosuppressive machinery for its original host human.

Bacterial endophytes benefit the host with protection against abiotic and biotic stresses and through increased plant growth. In this study, we screened novel endophytes for the ability to endophytically inhabit leaf tissues. Four endophytic bacteria were screened from the apoplastic fluids extracted from the uninfected upper leaves of Arabidopsis thaliana 3 days postinoculation (dpi) with Pseudomonas syringae pv. tomato DC3000 (Pst). Under sterile plant growth conditions, we showed that the four isolates proliferated intercellularly in the leaf tissues of A. thaliana. Based on 16S rRNA sequencing analysis, the identities of the inoculated endophytes and the re-isolates from the leaf tissues were confirmed. Among the isolates, the two species of Rhodococcus were the first members of the genus to be identified as leaf-inhabiting endophytes. Additionally, three of the isolates showed antagonistic activities, with different levels of activity, against Fusarium oxysporum pv. conglutinans (F.o.) and/or Pst. Furthermore, the application of one isolate, Bacillus cereus KB1, on tomato plants significantly increased the disease resistance to Botrytis cinerea and Pst. In combination, these results indicate that these endophytic isolates can be used to develop potential biocontrol agents against a variety of pathogenic fungi and bacteria.

The purpose of this research was to analyze the clothing behavioral attributes of male music enthusiasts. A questionnaire was developed based on previous researches. Respondents were men who were concerned with music in terms of a job, a major or a hobby. A total of 200 responses were analyzed by SPSS 20.0 through factor analysis with Varimax rotation, ANOVA with post-hoc test(SNK-test) and χ²-test. Music preference was classified into 3 factors: New age/jazz, Hiphop/dance, and Metal rock/ballad factor. 5 Clothing purchasing orientation factors were extruded: hedonic, planned, convenience, brand pursued, and fashion pursued purchasing orientation. Using those factor scores, 3 groups were classified: Group1(G1), preferring Hiphop/dance music with lower hedonic and brand/fashion pursued purchasing orientation; G2, preferring Hiphop/dance music with no interest in clothing shopping and fashion; G3, preferring New age music with high convenience and brand pursued purchasing orientation. In addition, there were significant differences among groups in clothing behavior such as social ostentation, individuality, self-expression, fashionability, conformity; in purchase motivation such as hedonic and trend/designer oriented purchase motivation; in information source like advertisement/media source; and in store choice criteria such as store light/music and popularity. The findings showed even the enthusiasts for the same music showed the different sopping orientation and different clothing behavior, suggesting that a personal value or taste can be a plausible factor to figure out attributes of consumers. An interest/involvement in clothing could be helpful to subdivide the music enthusiasts as the target market. Keywords: popular music, music enthusiast, clothing purchasing orientation, clothing behavior

Variovorax paradoxus KB5, isolated from the inside of Arabidopsis thaliana leaves, showed antibacterial activity against the phytopathogen Pseudomonas syringae pv. tomato DC3000. Here, we report a draft genome sequence of V. paradoxus KB5, which contains a delftibactin-like nonribosomal peptide biosynthetic gene cluster.

Alteration of macrophage function has an important regulatory impact on the survival of intracellular mycobacteria. We found that macrophages infected with attenuated Mycobacterium tuberculosis (Mtb) strain H37Ra had elevated expression of M1-related molecules, whereas the M2 phenotype was dominant in macrophages infected with virulent Mtb H37Rv. Further, the TLR signalling pathway played an important role in modulating macrophage polarization against Mtb infection. Interestingly, endoplasmic reticulum (ER) stress was significantly increased in M1 polarized macrophages and these macrophages effectively removed intracellular Mtb, indicating that ER stress may be an important component of the host immune response to Mtb in M1 macrophages. This improved understanding of the mechanisms that regulate macrophage polarization could provide new therapeutic strategies for tuberculosis.

Rhodococcus kyotonensis KB10 is an endophytic bacterium isolated from Arabidopsis thaliana . The organism showed mild antibacterial activity against the phytopathogen Pseudomonas syringae pv. tomato DC3000. This study reports the genome sequence of R. kyotonensis KB10. This bacterium contains an ectoine biosynthesis gene cluster and has the potential to degrade nitroaromatic compounds. The identified bacterium may be a suitable biocontrol agent and degrader of environmental pollutants.

Prostate apoptosis response-4 (Par-4) is a tumor suppressor protein that forms a complex with glucose-regulated protein 78 (GRP78) to induce apoptosis. Previously, we reported that ER stress-induced apoptosis is a critical host defense mechanism against Mycobacterium tuberculosis (Mtb). We sought to understand the role of Par-4 during ER stress-induced apoptosis in response to mycobacterial infection. Par-4 and GRP78 protein levels increased in response Mtb (strain: H37Ra) infection. Furthermore, Par-4 and GRP78 translocate to the surface of Mtb H37Ra-infected macrophages and induce apoptosis via caspase activation. NF-κB activation, Mtb-mediated ER stress, and Par-4 production were significantly diminished in macrophages with inhibited ROS production. To test Par-4 function during mycobacterial infection, we analyzed intracellular survival of Mtb H37Ra in macrophages with Par-4 overexpression or knockdown. Mtb H37Ra growth was significantly reduced in Par-4 overexpressing macrophages and increased in knockdown macrophages. We also observed increased Par-4, GRP78, and caspases activation in Bacillus Calmette-Guérin (BCG)-infected prostate cancer cells. Our data demonstrate that Par-4 is associated with ER stress-induced apoptosis resulting in reduced intracellular survival of mycobacteria. BCG treatment increases Par-4-dependent caspase activation in prostate cancer cells. These results suggest ER stress-induced Par-4 acts as an important defense mechanism against mycobacterial infection and regulates cancer.

Background: The purpose of the study was to understand how family physicians managed their primary health care centers and to identify the factors for successful management of their privative clinics. Methods: The data was collected through individual interviews from five family physicians who operated their private clinics. All interviews were tape-recorded and transcribed into verbatim data. The data was analyzed using qualitative content analysis. Results: Three major categories were identified: 1) types of physician based on major value as a doctor; 2) difficulties in operation and management; 3) desirable operating strategies for success. The first category described what kinds of value the physicians pursued as they operated their private clinics. Two different types were identified. One was intrinsic value oriented and the other was extrinsic value oriented. The second category illustrated many difficulties that family physicians faced in operating and managing their private clinics. Lack of private time, social isolation, and gap between mission and reality of practice were identified as major difficulties. Desirable strategies for the successful management were four subcategories: location; self-oriented developmental plan; specialization of the services; and activating network with larger hospitals. Conclusion: The results of the study would be helpful in setting up and operating private clinics through understanding the difficulties and strategies of primary physicians and recognizing mission and major value of them.