Improvement of the SOD activity of the Cu2+ complexes by hybridization with lysozyme and its hydrogen bond effect on the activity enhancement

We prepared L-amino acids (L-valine and L-serine, respectively) based on the Schiff base Cu2+ complexes CuSV and CuSS in the absence/presence of hydroxyl groups and their imidazole-bound compounds CuSV-Imi and CuSS-Imi to reveal the effects of hydroxyl groups on SOD activity. The structural and spectroscopic features of the Cu2+ complexes were evaluated using X-ray crystallography, UV-vis spectroscopy, and EPR spectroscopy. The spectroscopic behavior upon addition of lysozyme indicated that both CuSV and CuSS were coordinated by the imidazole group of His15 in lysozyme at their equatorial position, leading to the formation of hybrid proteins with lysozyme. CuSS-Imi showed a higher SOD activity than CuSV-Imi, indicating that the hydroxyl group of CuSS-Imi played an important role in the disproportionation of O2− ion. Hybridization of the Cu2+ complexes CuSV and CuSS with lysozyme resulted in higher SOD activity than that of CuSV-Imi and CuSS-Imi. The improvements in SOD activity suggest that there are cooperative effects between Cu2+ complexes and lysozyme

Growth of CrSi2 Nanostructures Using CrCl2 Powder on Si Substrates

Chromium disilicide (CrSi2) nanostructures were grown by the exposure of Si (111) substrates to CrCl2 vapor in an argon gas flow at atmospheric pressure without using any metal catalyst. Dependence of the growth condition on the structural property was investigated. Hexagonal-shaped CrSi2 microrods were grown at 750 °C with 0.05 g of CrCl2. As the quantity of CrCl2 increased to 0.1 g, the bundle of CrSi2 nanowires with microrods and web-liked CrSi2 nanostructure with turning angles were grown at 750 °C and 700 °C, respectively. The preliminary discussion on the growth mechanism of CrSi2 micro- and nanostructures was carried out

Thermosynechococcus switches the direction of phototaxis by a c-di-GMP-dependent process with high spatial resolution

Many cyanobacteria, which use light as an energy source via photosynthesis, show directional movement towards or away from a light source. However, the molecular and cell biological mechanisms for switching the direction of movement remain unclear. Here, we visualized type IV pilus-dependent cell movement in the rod-shaped thermophilic cyanobacterium Thermosynechococcus vulcanus using optical microscopy at physiological temperature and light conditions. Positive and negative phototaxis were controlled on a short time scale of 1 min. The cells smoothly moved over solid surfaces towards green light, but the direction was switched to backward movement when we applied additional blue light illumination. The switching was mediated by three photoreceptors, SesA, SesB, and SesC, which have cyanobacteriochrome photosensory domains and synthesis/degradation activity of the bacterial second messenger cyclic dimeric GMP (c-di-GMP). Our results suggest that the decision-making process for directional switching in phototaxis involves light-dependent changes in the cellular concentration of c-di-GMP. Direct visualization of type IV pilus filaments revealed that rod-shaped cells can move perpendicular to the light vector, indicating that the polarity can be controlled not only by pole-to-pole regulation but also within-a-pole regulation. This study provides insights into previously undescribed rapid bacterial polarity regulation via second messenger signalling with high spatial resolution

Growth of CrSi2 Nanostructures Using CrCl2 Powder on Si Substrates

Chromium disilicide (CrSi2) nanostructures were grown by the exposure of Si (111) substrates to CrCl2 vapor in an argon gas flow at atmospheric pressure without using any metal catalyst. Dependence of the growth condition on the structural property was investigated. Hexagonal-shaped CrSi2 microrods were grown at 750 °C with 0.05 g of CrCl2. As the quantity of CrCl2 increased to 0.1 g, the bundle of CrSi2 nanowires with microrods and web-liked CrSi2 nanostructure with turning angles were grown at 750 °C and 700 °C, respectively. The preliminary discussion on the growth mechanism of CrSi2 micro- and nanostructures was carried out.Keywords: CrSi2, microrods, nanostructures, thermoelectric materia

Lack of a surface layer in Tannerella forsythia mutants deficient in the type IX secretion system

Tannerella forsythia, a Gram-negative anaerobic bacterium, is an important pathogen in periodontal disease. This bacterium possesses genes encoding all known components of the type IX secretion system (T9SS). T. forsythia mutants deficient in genes orthologous to the T9SS-encoding genes porK, porT and sov were constructed. All porK, porT and sov single mutants lacked the surface layer (S-layer) and expressed less-glycosylated versions of the S-layer glycoproteins TfsA and TfsB. In addition, these mutants exhibited decreased haemagglutination and increased biofilm formation. Comparison of the proteins secreted by the porK and WT strains revealed that the secretion of several proteins containing C-terminal domain (CTD)-like sequences is dependent on the porK gene. These results indicate that the T9SS is functional in T. forsythia and contributes to the translocation of CTD proteins to the cell surface or into the extracellular milieu

Filamentous structures in the cell envelope are associated with bacteroidetes gliding machinery

Many bacteria belonging to the phylum Bacteroidetes move on solid surfaces, called gliding motility. In our previous study with the Bacteroidetes gliding bacterium Flavobacterium johnsoniae, we proposed a helical loop track model, where adhesive SprB filaments are propelled along a helical loop on the cell surface. In this study, we observed the gliding cell rotating counterclockwise about its axis when viewed from the rear to the advancing direction of the cell and revealed that one labeled SprB focus sometimes overtook and passed another SprB focus that was moving in the same direction. Several electron microscopic analyses revealed the presence of a possible multi-rail structure underneath the outer membrane, which was associated with SprB filaments and contained GldJ protein. These results provide insights into the mechanism of Bacteroidetes gliding motility, in which the SprB filaments are propelled along tracks that may form a multi-rail system underneath the outer membrane. The insights may give clues as to how the SprB filaments get their driving force

Tree of motility – A proposed history of motility systems in the tree of life

Motility often plays a decisive role in the survival of species. Five systems of motility have been studied in depth: those propelled by bacterial flagella, eukaryotic actin polymerization and the eukaryotic motor proteins myosin, kinesin and dynein. However, many organisms exhibit surprisingly diverse motilities, and advances in genomics, molecular biology and imaging have showed that those motilities have inherently independent mechanisms. This makes defining the breadth of motility nontrivial, because novel motilities may be driven by unknown mechanisms. Here, we classify the known motilities based on the unique classes of movement-producing protein architectures. Based on this criterion, the current total of independent motility systems stands at 18 types. In this perspective, we discuss these modes of motility relative to the latest phylogenetic Tree of Life and propose a history of motility. During the ~4 billion years since the emergence of life, motility arose in Bacteria with flagella and pili, and in Archaea with archaella. Newer modes of motility became possible in Eukarya with changes to the cell envelope. Presence or absence of a peptidoglycan layer, the acquisition of robust membrane dynamics, the enlargement of cells and environmental opportunities likely provided the context for the (co)evolution of novel types of motility

A prospective compound screening contest identified broader inhibitors for Sirtuin 1

Potential inhibitors of a target biomolecule, NAD-dependent deacetylase Sirtuin 1, were identified by a contest-based approach, in which participants were asked to propose a prioritized list of 400 compounds from a designated compound library containing 2.5 million compounds using in silico methods and scoring. Our aim was to identify target enzyme inhibitors and to benchmark computer-aided drug discovery methods under the same experimental conditions. Collecting compound lists derived from various methods is advantageous for aggregating compounds with structurally diversified properties compared with the use of a single method. The inhibitory action on Sirtuin 1 of approximately half of the proposed compounds was experimentally accessed. Ultimately, seven structurally diverse compounds were identified

Spherical Lactic Acid Bacteria Activate Plasmacytoid Dendritic Cells Immunomodulatory Function via TLR9-Dependent Crosstalk with Myeloid Dendritic Cells

Plasmacytoid dendritic cells (pDC) are a specialized sensor of viral and bacterial nucleic acids and a major producer of IFN-α that promotes host defense by priming both innate and acquired immune responses. Although synthetic Toll-like receptor (TLR) ligands, pathogenic bacteria and viruses activate pDC, there is limited investigation of non-pathogenic microbiota that are in wide industrial dietary use, such as lactic acid bacteria (LAB). In this study, we screened for LAB strains, which induce pDC activation and IFN-α production using murine bone marrow (BM)-derived Flt-3L induced dendritic cell culture. Microbial strains with such activity on pDC were absent in a diversity of bacillary strains, but were observed in certain spherical species (Lactococcus, Leuconostoc, Streptococcus and Pediococcus), which was correlated with their capacity for uptake by pDC. Detailed study of Lactococcus lactis subsp. lactis JCM5805 and JCM20101 revealed that the major type I and type III interferons were induced (IFN-α, -β, and λ). IFN-α induction was TLR9 and MyD88-dependent; a slight impairment was also observed in TLR4-/- cells. While these responses occurred with purified pDC, IFN-α production was synergistic upon co-culture with myeloid dendritic cells (mDC), an interaction that required direct mDC-pDC contact. L. lactis strains also stimulated expression of immunoregulatory receptors on pDC (ICOS-L and PD-L1), and accordingly augmented pDC induction of CD4+CD25+FoxP3+ Treg compared to the Lactobacillus strain. Oral administration of L. lactis JCM5805 induced significant activation of pDC resident in the intestinal draining mesenteric lymph nodes, but not in a remote lymphoid site (spleen). Taken together, certain non-pathogenic spherical LAB in wide dietary use has potent and diverse immunomodulatory effects on pDC potentially relevant to anti-viral immunity and chronic inflammatory disease

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020)

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created as revised from J-SSCG 2016 jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in September 2020 and published in February 2021. An English-language version of these guidelines was created based on the contents of the original Japanese-language version. The purpose of this guideline is to assist medical staff in making appropriate decisions to improve the prognosis of patients undergoing treatment for sepsis and septic shock. We aimed to provide high-quality guidelines that are easy to use and understand for specialists, general clinicians, and multidisciplinary medical professionals. J-SSCG 2016 took up new subjects that were not present in SSCG 2016 (e.g., ICU-acquired weakness [ICU-AW], post-intensive care syndrome [PICS], and body temperature management). The J-SSCG 2020 covered a total of 22 areas with four additional new areas (patient- and family-centered care, sepsis treatment system, neuro-intensive treatment, and stress ulcers). A total of 118 important clinical issues (clinical questions, CQs) were extracted regardless of the presence or absence of evidence. These CQs also include those that have been given particular focus within Japan. This is a large-scale guideline covering multiple fields; thus, in addition to the 25 committee members, we had the participation and support of a total of 226 members who are professionals (physicians, nurses, physiotherapists, clinical engineers, and pharmacists) and medical workers with a history of sepsis or critical illness. The GRADE method was adopted for making recommendations, and the modified Delphi method was used to determine recommendations by voting from all committee members.As a result, 79 GRADE-based recommendations, 5 Good Practice Statements (GPS), 18 expert consensuses, 27 answers to background questions (BQs), and summaries of definitions and diagnosis of sepsis were created as responses to 118 CQs. We also incorporated visual information for each CQ according to the time course of treatment, and we will also distribute this as an app. The J-SSCG 2020 is expected to be widely used as a useful bedside guideline in the field of sepsis treatment both in Japan and overseas involving multiple disciplines.other authors: Satoru Hashimoto,Daisuke Hasegawa,Junji Hatakeyama,Naoki Hara,Naoki Higashibeppu,Nana Furushima,Hirotaka Furusono,Yujiro Matsuishi,Tasuku Matsuyama,Yusuke Minematsu,Ryoichi Miyashita,Yuji Miyatake,Megumi Moriyasu,Toru Yamada,Hiroyuki Yamada,Ryo Yamamoto,Takeshi Yoshida,Yuhei Yoshida,Jumpei Yoshimura,Ryuichi Yotsumoto,Hiroshi Yonekura,Takeshi Wada,Eizo Watanabe,Makoto Aoki,Hideki Asai,Takakuni Abe,Yutaka Igarashi,Naoya Iguchi,Masami Ishikawa,Go Ishimaru,Shutaro Isokawa,Ryuta Itakura,Hisashi Imahase,Haruki Imura,Takashi Irinoda,Kenji Uehara,Noritaka Ushio,Takeshi Umegaki,Yuko Egawa,Yuki Enomoto,Kohei Ota,Yoshifumi Ohchi,Takanori Ohno,Hiroyuki Ohbe,Kazuyuki Oka,Nobunaga Okada,Yohei Okada,Hiromu Okano,Jun Okamoto,Hiroshi Okuda,Takayuki Ogura,Yu Onodera,Yuhta Oyama,Motoshi Kainuma,Eisuke Kako,Masahiro Kashiura,Hiromi Kato,Akihiro Kanaya,Tadashi Kaneko,Keita Kanehata,Ken-ichi Kano,Hiroyuki Kawano,Kazuya Kikutani,Hitoshi Kikuchi,Takahiro Kido,Sho Kimura,Hiroyuki Koami,Daisuke Kobashi,Iwao Saiki,Masahito Sakai,Ayaka Sakamoto,Tetsuya Sato,Yasuhiro Shiga,Manabu Shimoto,Shinya Shimoyama,Tomohisa Shoko,Yoh Sugawara,Atsunori Sugita,Satoshi Suzuki,Yuji Suzuki,Tomohiro Suhara,Kenji Sonota,Shuhei Takauji,Kohei Takashima,Sho Takahashi,Yoko Takahashi,Jun Takeshita,Yuuki Tanaka,Akihito Tampo,Taichiro Tsunoyama,Kenichi Tetsuhara,Kentaro Tokunaga,Yoshihiro Tomioka,Kentaro Tomita,Naoki Tominaga,Mitsunobu Toyosaki,Yukitoshi Toyoda,Hiromichi Naito,Isao Nagata,Tadashi Nagato,Yoshimi Nakamura,Yuki Nakamori,Isao Nahara,Hiromu Naraba,Chihiro Narita,Norihiro Nishioka,Tomoya Nishimura,Kei Nishiyama,Tomohisa Nomura,Taiki Haga,Yoshihiro Hagiwara,Katsuhiko Hashimoto,Takeshi Hatachi,Toshiaki Hamasaki,Takuya Hayashi,Minoru Hayashi,Atsuki Hayamizu,Go Haraguchi,Yohei Hirano,Ryo Fujii,Motoki Fujita,Naoyuki Fujimura,Hiraku Funakoshi,Masahito Horiguchi,Jun Maki,Naohisa Masunaga,Yosuke Matsumura,Takuya Mayumi,Keisuke Minami,Yuya Miyazaki,Kazuyuki Miyamoto,Teppei Murata,Machi Yanai,Takao Yano,Kohei Yamada,Naoki Yamada,Tomonori Yamamoto,Shodai Yoshihiro,Hiroshi Tanaka,Osamu NishidaGuideline