DAT (deacylating autotransporter toxin) from Bordetella parapertussis demyristoylates Gαi GTPases and contributes to cough

The pathogenic bacteria Bordetella pertussis and Bordetella parapertussis cause pertussis (whooping cough) and pertussis-like disease, respectively, both of which are characterized by paroxysmal coughing. We previously reported that pertussis toxin (PTx), which inactivates heterotrimeric GTPases of the Gi family through ADP-ribosylation of their α subunits, causes coughing in combination with Vag8 and lipid A in B. pertussis infection. In contrast, the mechanism of cough induced by B. parapertussis, which produces Vag8 and lipopolysaccharide (LPS) containing lipid A, but not PTx, remained to be elucidated. Here, we show that a toxin we named deacylating autotransporter toxin (DAT) of B. parapertussis inactivates heterotrimeric Gi GTPases through demyristoylation of their α subunits and contributes to cough production along with Vag8 and LPS. These results indicate that DAT plays a role in B. parapertussis infection in place of PTx.Hiramatsu Y., Nishida T., Ota N., et al. DAT (deacylating autotransporter toxin) from Bordetella parapertussis demyristoylates Gαi GTPases and contributes to cough. Proceedings of the National Academy of Sciences of the United States of America 120, e2308260120 (2023); https://doi.org/10.1073/pnas.2308260120

Kansai University Library 100th anniversary

目次 【序文】記念誌の刊行にあたって（図書館長　内田慶市）図書館創設100周年によせて（学長　楠見晴重）記念誌の編集について【第1部　この20年を振り返って】高槻図書室開館（広瀬雅子）…3阪神・淡路大震災（高橋真澄）…8図書館システムの変遷（徳岡久実・濱生快彦）…12図書館ビジョン7項目の制定（濱生快彦）…20図書館におけるアウトソーシング（高橋真澄）…26電子展示（濱生快彦）…36市民利用開始（広瀬雅子）…41図書館ウェブサイト（濱生快彦）…442010プロジェクトによる新図書館（高橋真澄・田中恵美）…48図書館リニューアル工事（新谷大二郎）…60図書館の現在と未来（堀口和弘）…68【第2部　図書館に想う】関西大学図書館創設100周年に寄せて（市川訓敏）…79図書館の思い出、図書館への思い（北川勝彦）…85図書館在職時の思い出（柴田真一）…91数々の貴重書（田中登）…95関西大学図書館100周年にあたって : 私の夢想する図書館（内田慶市）…100【第3部　図書館の文庫・コレクション】文庫・コレクションの紹介（鵜飼香織）…111【第4部　資料編】図書館年譜（明治19.3 ～平成26.7）…119サービスに係る統計（総合図書館）…146サービスに係る統計（高槻図書室・ミューズ大学図書館・堺キャンパス図書館）…148蔵書数の推移…149図書費執行額の推移…150展示一覧…152他大学図書館との協定一覧…160【「図書館コラム」】新人時代の思い出（高松和美）…11エレベーターにまつわる話（吉田有輝）…19泣き別れたり、親子になったり（嶋田有理香）…35貴重なのは本だけ？貴重書担当のつぶやき（大上良樹）…40会長校のころ（金東瀅）…46『コアラ博士』にまつわるあれこれ（松本和剛）…57広報誌『KULione 』誕生秘話（白髪友賀）…59本と夢を運んだテレリフト（芝谷秀司）…66LOUIS VUITTON（加藤博之）…7

Association of <it>Bordetella </it>dermonecrotic toxin with the extracellular matrix

Abstract Background Bordetella dermonecrotic toxin (DNT) causes the turbinate atrophy in swine atrophic rhinitis, caused by a Bordetella bronchiseptica infection of pigs, by inhibiting osteoblastic differentiation. The toxin is not actively secreted from the bacteria, and is presumed to be present in only small amounts in infected areas. How such small amounts can affect target tissues is unknown. Results Fluorescence microscopy revealed that DNT associated with a fibrillar structure developed on cultured cells. A cellular component cross-linked with DNT conjugated with a cross-linker was identified as fibronectin by mass spectrometry. Colocalization of the fibronectin network on the cells with DNT was also observed by fluorescence microscope. Several lines of evidence suggested that DNT interacts with fibronectin not directly, but through another cellular component that remains to be identified. The colocalization was observed in not only DNT-sensitive cells but also insensitive cells, indicating that the fibronectin network neither serves as a receptor for the toxin nor is involved in the intoxicating procedures. The fibronectin network-associated toxin was easily liberated when the concentration of toxin in the local environment decreased, and was still active. Conclusions Components in the extracellular matrix are known to regulate activities of various growth factors by binding and liberating them in response to alterations in the extracellular environment. Similarly, the fibronectin-based extracellular matrix may function as a temporary storage system for DNT, enabling small amounts of the toxin to efficiently affect target tissues or cells.</p

Crystallization and preliminary crystallographic studies of the Pasteurella multocida toxin catalytic domain

The C-terminal catalytic domain of P. multocida toxin, which is the virulence factor of the organism in P. multocida, has been expressed, purified and subsequently crystallized using the sitting-drop vapour-diffusion technique