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981.
Jisub Hwang Chang-Sook Jeong Chang Woo Lee Seung Chul Shin Han-Woo Kim Sung Gu Lee Ui Joung Youn Chang Sup Lee Tae-Jin Oh Hak Jun Kim Hyun Park Hyun Ho Park Jun Hyuck Lee 《Journal of microbiology (Seoul, Korea)》2020,58(7):606-613
Crystal structures of enoyl-coenzyme A (CoA) isomerase from Bosea sp. PAMC 26642 (BoECI) and enoyl-CoA hydratase from Hymenobacter sp. PAMC 26628 (HyECH) were determined at 2.35 and 2.70 Å resolution, respectively. BoECI and HyECH are members of the crotonase superfamily and are enzymes known to be involved in fatty acid degradation. Structurally, these enzymes are highly similar except for the orientation of their C-terminal helix domain. Analytical ultracentrifugation was performed to determine the oligomerization states of BoECI and HyECH revealing they exist as trimers in solution. However, their putative ligand-binding sites and active site residue compositions are dissimilar. Comparative sequence and structural analysis revealed that the active site of BoECI had one glutamate residue (Glu135), this site is occupied by an aspartate in some ECIs, and the active sites of HyECH had two highly conserved glutamate residues (Glu118 and Glu138). Moreover, HyECH possesses a salt bridge interaction between Glu98 and Arg152 near the active site. This interaction may allow the catalytic Glu118 residue to have a specific conformation for the ECH enzyme reaction. This salt bridge interaction is highly conserved in known bacterial ECH structures and ECI enzymes do not have this type of interaction. Collectively, our comparative sequential and structural studies have provided useful information to distinguish and classify two similar bacterial crotonase superfamily enzymes. 相似文献
982.
Soo Min Kim Iliana Escorbar Kiho Lee Beth Burgwyn Fuchs Eleftherios Mylonakis Wooseong Kim 《Journal of microbiology (Seoul, Korea)》2020,58(6):431-444
Staphylococcus aureus is a leading cause of hospital- and community-acquired infections. Despite current advances in antimicrobial chemotherapy, the infections caused by S. aureus remain challenging due to their ability to readily develop resistance. Indeed, antibiotic resistance, exemplified by methicillin-resistant S. aureus (MRSA) is a top threat to global health security. Furthermore, the current rate of antibiotic discovery is much slower than the rate of antibiotic-resistance development. It seems evident that the conventional in vitro bacterial growth-based screening strategies can no longer effectively supply new antibiotics at the rate needed to combat bacterial antibiotic-resistance. To overcome this antibiotic resistance crisis, screening assays based on host–pathogen interactions have been developed. In particular, the free-living nematode Caenorhabditis elegans has been used for drug screening against MRSA. In this review, we will discuss the general principles of the C. elegans-based screening platform and will highlight its unique strengths by comparing it with conventional antibiotic screening platforms. We will outline major hits from high-throughput screens of more than 100,000 small molecules using the C. elegans–MRSA infection assay and will review the mode-of-action of the identified hit compounds. Lastly, we will discuss the potential of a C. elegans-based screening strategy as a paradigm shift screening platform. 相似文献
983.
Won Yu Jung Kang Lae Hyung Lee Ah Ra Paik Bomina Kim Hyun Lee Sung Geun Park Seung Won Hong Seung Jin Paik Soon Young 《Journal of microbiology (Seoul, Korea)》2020,58(5):422-429
Journal of Microbiology - Enterovirus A71 (EV71), the main etiological agent of handfoot- mouth disease (HFMD), circulates in many areas of the world and has caused large epidemics since 1997,... 相似文献
984.
985.
Kim Seho Park Juhee Kim Taekyung Lee Jung-Shin 《Journal of microbiology (Seoul, Korea)》2020,58(5):343-349
Journal of Microbiology - The functional and optimal expression of genes is crucial for survival of all living organisms. Numerous experiments and efforts have been performed to reveal the... 相似文献
986.
Woo Ryung Kim Eun Gyung Park Kyung-Won Kang Sang-Myeong Lee Bumseok Kim Heui-Soo Kim 《Molecules and cells》2020,43(11):953
Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an infectious disease with multiple severe symptoms, such as fever over 37.5°C, cough, dyspnea, and pneumonia. In our research, microRNAs (miRNAs) binding to the genome sequences of severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory-related coronavirus (MERS-CoV), and SARS-CoV-2 were identified by bioinformatic tools. Five miRNAs (hsa-miR-15a-5p, hsa-miR-15b-5p, hsa-miR-195-5p, hsa-miR-16-5p, and hsa-miR-196a-1-3p) were found to commonly bind to SARS-CoV, MERS-CoV, and SARS-CoV-2. We also identified miRNAs that bind to receptor proteins, such as ACE2, ADAM17, and TMPRSS2, which are important for understanding the infection mechanism of SARS-CoV-2. The expression patterns of those miRNAs were examined in hamster lung samples infected by SARS-CoV-2. Five miRNAs (hsa-miR-15b-5p, hsa-miR-195-5p, hsa-miR-221-3p, hsa-miR-140-3p, and hsa-miR-422a) showed differential expression patterns in lung tissues before and after infection. Especially, hsa-miR-15b-5p and hsa-miR-195-5p showed a large difference in expression, indicating that they may potentially be diagnostic biomarkers for SARS-CoV-2 infection. 相似文献
987.
Mi Hye Kim Jae Yeop Kim Jung‐Hak Kim Hyun‐Shik Lee Jae‐Won Huh Dong‐Seok Lee 《Cell biology international》2020,44(10):2086-2093
Reactive oxygen species (ROS) act as signaling molecules to regulate various cell functions. Numerous studies have demonstrated ROS to be essential for the differentiation of adipocytes. Peroxiredoxins (Prxs) are a ubiquitous family of antioxidant enzymes in mammalian cells. Prx2 is present in the cytoplasm and cell membranes and demonstrates ROS scavenging activity. We focused on Prx2 involvement in regulating adipogenesis and lipid accumulation and demonstrated that Prx2 expression was upregulated during adipocyte differentiation. In addition, the silencing of Prx2 (shPrx2) inhibited adipogenesis by modulating adipogenic gene expression, and cell death was enhanced via increased ROS production in shPrx2‐3T3‐L1 cells. These results demonstrate that shPrx2 triggers adipocyte cell death and weakens adipocyte function via ROS production. Taken together, our data suggest the participation of Prx2 in adipocyte function and differentiation. Our results also imply that the downregulation of Prx2 activity could help prevent obesity. Overall, findings support the development of ROS‐based therapeutic solutions for the treatment of obesity and obesity‐related metabolic disorders. 相似文献
988.
William E. Kumler Justin Jorge Paul M. Kim Noama Iftekhar M. A. R. Koehl 《The Journal of eukaryotic microbiology》2020,67(5):555-565
Microbial eukaryotes, critical links in aquatic food webs, are unicellular, but some, such as choanoflagellates, form multicellular colonies. Are there consequences to predator avoidance of being unicellular vs. forming larger colonies? Choanoflagellates share a common ancestor with animals and are used as model organisms to study the evolution of multicellularity. Escape in size from protozoan predators is suggested as a selective factor favoring evolution of multicellularity. Heterotrophic protozoans are categorized as suspension feeders, motile raptors, or passive predators that eat swimming prey which bump into them. We focused on passive predation and measured the mechanisms responsible for the susceptibility of unicellular vs. multicellular choanoflagellates, Salpingoeca helianthica, to capture by passive heliozoan predators, Actinosphaerium nucleofilum, which trap prey on axopodia radiating from the cell body. Microvideography showed that unicellular and colonial choanoflagellates entered the predator's capture zone at similar frequencies, but a greater proportion of colonies contacted axopodia. However, more colonies than single cells were lost during transport by axopodia to the cell body. Thus, feeding efficiency (proportion of prey entering the capture zone that were engulfed in phagosomes) was the same for unicellular and multicellular prey, suggesting that colony formation is not an effective defense against such passive predators. 相似文献
989.
Woo Yong Sung Ji Won Yu Jong Tae Hwang Hee Jin Nam Ji Ye Park Yongae Kim Jang‐Hee Cho 《Journal of peptide science》2020,26(8)
Antimicrobial peptides are class of small, positively charged peptides known for their broad‐spectrum antimicrobial activity. Antimicrobial activities for most antimicrobial peptides have largely remained elusive, particularly in the lactic acid bacteria. However, recently our investigation using LPcin‐YK3, an antimicrobial peptide from bovine milk, suggests that in vitro antimicrobial activity was reduced over 100‐fold compared with pathogenic bacteria. Additionally, for the structural study of how antimicrobial peptide undergoes its reaction at the proteolytic pathway of lactic acid bacteria based on degradation assay and propidium iodide staining, we performed molecular docking for interaction between oligopeptide‐binding protein A and LPcin‐YK3 peptide. Given that degradation related to the LPcin‐YK3 peptide in lactic acid bacteria proteolytic system, the inhibitory inactivity of LPcin‐YK3 against beneficial lactic acid bacteria strains may be one of the primary pharmacological properties of recombinant peptide discovered in bovine milk. These results provide structural and functional insights into the proteolytic mechanism and possibility as a putative substrate of oligopeptide‐binding protein A in respect of LPcin‐YK3 peptide. 相似文献
990.