||Seung Ah Lee, Seong Han Jang, Byung Hyun Kim, Toshio Shibata, Jinwook Yoo, Yunjin Jung, Shun-Ichiro Kawabata, Bok Luel Lee, Insecticidal activity of the metalloprotease AprA occurs through suppression of host cellular and humoral immunity, Developmental and Comparative Immunology, 10.1016/j.dci.2017.11.014, 81, 116-126, 2018.04, The biochemical characterization of virulence factors from entomopathogenic bacteria is important to understand entomopathogen-insect molecular interactions. Pseudomonas entomophila is a typical entomopathogenic bacterium that harbors virulence factors against several insects. However, the molecular actions of these factors against host innate immune responses are not clearly elucidated. In this study, we observed that bean bugs (Riptortus pedestris) that were injected with P. entomophila were highly susceptible to this bacterium. To determine how P. entomophila counteracts the host innate immunity to survive within the insect, we purified a highly enriched protein with potential host insect-killing activity from the culture supernatant of P. entomophila. Then, a 45-kDa protein was purified to homogeneity and identified as AprA which is an alkaline zinc metalloprotease of the genus Pseudomonas by liquid chromatography mass spectrometry (LC-MS). Purified AprA showed a pronounced killing effect against host insects and suppressed both host cellular and humoral innate immunity. Furthermore, to show that AprA is an important insecticidal protein of P. entomophila, we used an aprA-deficient P. entomophila mutant strain (ΔaprA). When ΔaprA mutant cells were injected to host insects, this mutant exhibited extremely attenuated virulence. In addition, the cytotoxicity against host hemocytes and the antimicrobial peptide-degrading ability of the ΔaprA mutant were greatly decreased. These findings suggest that AprA functions as an important insecticidal protein of P. entomophila via suppression of host cellular and humoral innate immune responses..
||Shun Ichiro Kawabata, Toshio Shibata, Purification and Assays of Tachylectin-2, Methods in molecular biology (Clifton, N.J.), 10.1007/978-1-0716-0430-4_30, 2132, 309-316, 2020.01, Tachylectin-2, a 27-kDa protein consisting of a five-bladed β-propeller structure, is purified by three steps of chromatography, including dextran sulfate-Sepharose CL-6B, CM-Sepharose CL-6B, and Mono S. Three isolectins of tachylectin-2 including tachylectin-2a, -2b, and -2c are purified. These isolectins exhibit hemagglutinating activity against human A-type erythrocytes in a Ca2+-independent manner with tachylectin-2b showing the highest activity. Tachylectin-2b specifically agglutinates Staphylococcus saprophyticus KD. The tachylectin-2b-mediated hemagglutination is inhibited in the presence of GlcNAc and GalNAc. The association constants for GlcNAc and GalNAc are Ka = 1.95 × 104 M-1 and Ka = 1.11 × 103 M-1, respectively. Ultracentrifugation analysis shows that tachylectin-2b is present in monomer form in solution..
||Toshio Shibata, Jinki Hadano, Daichi Kawasaki, Xiaoqing, Shun-ichiro Kawabata, Drosophila TG-A transglutaminase is secreted via an unconventional Golgi-independent mechanism involving exosomes and two types of fatty acylations, The Journal of Biological Chemistry, 10.1074/jbc.M117.779710, 292, 10723-10734, 2017.06.
||Kouki Maki, Toshio Shibata, Shun-ichiro Kawabata, Transglutaminase-catalyzed incorporation of polyamines masks the DNA-binding region of the transcription factor Relish, The Journal of Biological Chemistry, 10.1074/jbc.M117.779579, 292, 15, 6369-6380, 2017.04.
||Sanae Sekihara, Toshio Shibata, Mai Hyakkendani, Shun-ichiro Kawabata, RNA Interference Directed against the Transglutaminase Gene Triggers Dysbiosis of Gut Microbiota in Drosophila, The Journal of Biological Chemistry, 10.1074/jbc.M116.761791, 291, 48, 25077-25087, 2016.11.
||Toshio Shibata, Kouki Maki, Jinki Hadano, Takumi Fujikawa, Kazuki Kitazaki, Takumi Koshiba, Shun-ichiro Kawabata, Crosslinking of a Peritrophic Matrix Protein Protects Gut Epithelia from Bacterial Exotoxins, PLOS Pathogens, 10.1371/journal.ppat.1005244, 11, 10, e1005244, 2015.10.
||Yuki Kobayashi, Toshiaki Takahashi, Toshio Shibata, Shunsuke Ikeda, Takumi Koshiba, Hikaru Mizumura, Toshio Oda, Shun-ichiro Kawabata, Factor B Is the Second Lipopolysaccharide-binding Protease Zymogen in the Horseshoe Crab Coagulation Cascade., The Journal of Biological Chemistry, 10.1074/jbc.M115.653196, 290, 19379-19386, 2015.06.
||Yuki Kobayashi, Takafumi Shiga, Toshio Shibata, Miyuki Sako, Katsumi Maenaka, Takumi Koshiba, Hikaru Mizumura, Toshio Oda, Shun-ichiro Kawabata, The N-terminal Arg Residue Is Essential for Autocatalytic Activation of a Lipopolysaccharide-responsive Protease Zymogen, The Journal of Biological Chemistry, 289, 25987-25995, 2014.09.
||Toshio Shibata, Sanae Sekihara, Takumi Fujikawa, Ryuta Miyaji, Kouki Maki, Takeshi Ishihara, Takumi Koshiba, Shun-ichiro Kawabata, Transglutaminase-catalyzed protein-protein crosslinking suppresses the activity of the NF-κB-like transcription factor Relish, Science Signaling, 10.1126/scisignal.2003970, 6, ra61, 2013.07.
||Toshio Shibata, Shigeru Ariki, Shinzawa Naoaki, Ryuta Miyaji, Haruka Suyama, Miyuki Sako, Nobuyuki Inomata, Takumi Koshiba, Shun-ichiro Kawabata, Protein Crosslinking by Transglutaminase Controls Cuticle Morphogenesis in Drosophila, PLOS One, 10.1371/journal.pone.0013477, 5, 10, e13477, 2010.10.