Article
Biochemistry & Molecular Biology
Tatsuro Nishikino, Norihiro Takekawa, Duy Phuoc Tran, Jun-ichi Kishikawa, Mika Hirose, Sakura Onoe, Seiji Kojima, Michio Homma, Akio Kitao, Takayuki Kato, Katsumi Imada
Summary: Motile bacteria swim towards favorable environments using a rotating flagellum driven by a motor. The motor consists of a rotor and a stator, with the torque generated by the interaction between the rotor and the stator induced by ion flow. Recent cryo-EM studies on the stators from mesophiles revealed their composition, while low-resolution EM analysis showed that hyperthermophilic MotA forms a tetramer. The cryo-EM structure of MotA from the hyperthermophilic bacterium Aquifex aeolicus (Aa-MotA) was determined, showing it forms a pentamer and can assemble into a stator complex without MotB. The hydrophobic nature of MotA is crucial for stabilizing hyperthermophilic Aa-MotA.
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Ruben Perez-Carrasco, Maria-Jose Franco-Onate, Jean-Charles Walter, Jerome Dorignac, Fred Geniet, John Palmeri, Andrea Parmeggiani, Nils-Ole Walliser, Ashley L. Nord
Summary: This article focuses on the dynamics of bacterial flagellar motors, revealing a stoichiometry-dependent asymmetry in stator remodeling kinetics and proposing a two-state catch-bond mechanism to explain the observed asymmetry.
Article
Biology
Yumi Inoue, Miki Kinoshita, Mamoru Kida, Norihiro Takekawa, Keiichi Namba, Katsumi Imada, Tohru Minamino
Summary: Inoue and Kinoshita et al. report on the essential role of the flexible linker of FlhA (FlhA(L)) in regulating the switch from secretion of hook-type to filament-type components in the flagellar protein export apparatus. This study enhances our understanding of the intricate process of bacterial flagellar assembly.
COMMUNICATIONS BIOLOGY
(2021)
Article
Multidisciplinary Sciences
Kenta I. Ito, Shuichi Nakamura, Shoichi Toyabe
Summary: Cooperativity plays a central role in biological regulation, providing robust and highly-sensitive regulation. The bacterial flagellar motor regulates torque autonomously based on the dynamic structure of the stator, with a cooperative mechanism in the assembly dynamics. External load triggers dynamic remodeling of the molecular complex sustaining torque, and non-equilibrium allostery leads to an avalanche of succeeding bindings.
NATURE COMMUNICATIONS
(2021)
Article
Microbiology
Tsai-Shun Lin, Seiji Kojima, Hajime Fukuoka, Akihiko Ishijima, Michio Homma, Chien-Jung Lo
Summary: The bacterial flagellar motor (BFM) is a large membrane-spanning molecular rotary machine that adjusts the number of stator units to compensate for changes in external load and ion-motive force to maintain constant speed over a wide range of sodium concentrations. When rapidly transitioning from high to low sodium concentrations, the number of functional stator units experiences a rapid excessive reduction followed by resurrection, implying the presence of a metastable hidden state during the sudden loss of sodium ions.
FRONTIERS IN MICROBIOLOGY
(2021)
Article
Biochemistry & Molecular Biology
Jiaxing Tan, Xing Zhang, Xiaofei Wang, Caihuang Xu, Shenghai Chang, Hangjun Wu, Ting Wang, Huihui Liang, Haichun Gao, Yan Zhou, Yongqun Zhu
Summary: This study provides detailed molecular insights into the structure, assembly, and torque transmission mechanisms of the bacterial flagellar motor.
Review
Microbiology
Xiaotian Zhou, Anna Roujeinikova
Summary: Recent studies have shown the presence of additional periplasmic structures in polar flagellar motors, such as disk or cage-like morphologies, which are crucial for motor assembly and function. These structures enable polar flagellar motors to sustain higher torque and achieve faster swimming speeds compared to peritrichous bacteria.
FRONTIERS IN MICROBIOLOGY
(2021)
Article
Biology
Hideyuki Matsunami, Young-Ho Yoon, Katsumi Imada, Keiichi Namba, Fadel A. Samatey
Summary: The crystal structure of the flagellar hook cap from Salmonella enterica was determined by X-ray crystallography, revealing insights into a putative hook assembly mechanism. The pentameric structure of the hook cap, divided into a stalk region and a petal region, plays a key role in facilitating the assembly of the hook. The N-terminal domains of the hook cap are essential for its hook-capping function, and a plausible hook assembly mechanism promoted by the hook cap is proposed based on the structure.
COMMUNICATIONS BIOLOGY
(2021)
Article
Microbiology
Yuansheng Cao, Tairan Li, Yuhai Tu
Summary: This article develops a mathematical model for the rotary bacterial flagellar motor based on the structure of the stator complex. The model predicts distinctive dynamics and load dependence of the rotor and stator, which can be tested by future experiments.
FRONTIERS IN MICROBIOLOGY
(2022)
Article
Chemistry, Physical
Y. C. Chou
Summary: This study proposes a physical mechanism for the torque generation of a bacterial flagellar motor (BFM) by collisions between the stator and rotor, which can generate the impulsive forces required for rotor rotation. It suggests that two mechanisms, asymmetrical rotor fluctuation and collisions between the stator and asymmetric FliG(N) and FliG(M), can generate the torque in the direction of the rotor. These mechanisms may be related to bidirectional rotation, tumbling motion, and the characteristics of the rotational angle.
EUROPEAN PHYSICAL JOURNAL E
(2022)
Article
Microbiology
Sandra Sanchez, Caroline M. Dunn, Daniel B. Kearns
Summary: This study identifies the lytic transglycosylase CwlQ as a critical enzyme for flagellum-dependent swarming motility in Gram-negative bacteria, while the lyase essential for flagellar insertion in Gram-positive bacteria remains unknown. Even when mutated in combination with other lyases related to motility, CwlQ mutation does not affect flagellar biosynthesis in Gram-positive bacteria.
JOURNAL OF BACTERIOLOGY
(2021)
Article
Microbiology
Hiroyuki Terashima, Seiji Kojima, Michio Hommaa
Summary: The study directly demonstrates the physical interaction between specific residues in FliG and PomA/MotA using site-directed photo-cross-linking and disulfide cross-linking methods. The results provide insight into how stator units assemble around the rotor and generate torque in the bacterial flagellar motor.
JOURNAL OF BACTERIOLOGY
(2021)
Article
Multidisciplinary Sciences
Abhinav Adhikari, William Kim, Judith Davie
Summary: The skeletal muscle gene expression is regulated by the myogenic regulatory family (MRF) with key factors MyoD and myogenin (MYOG). MYOG is essential for recruiting TBP and RNAPII to muscle gene promoters, while MyoD1 and MYOG act in a feed forward loop to maintain each other's expression. The study demonstrates that MYOG, not MYOD1, is required to activate gene expression on late muscle gene promoters bound by both factors.
Article
Engineering, Environmental
Yingjie Liu, Tongtao Yue, Lu Liu, Bowen Zhang, Hao Feng, Shixin Li, Xia Liu, Yanhui Dai, Jian Zhao
Summary: Extracellular polymeric substances (EPS) play a significant role in modifying the fate and toxicity of nanoplastics at the microbial-aquatic interface. Through molecular dynamics simulations and experiments, this study provides insights into the assembly of EPS and its regulatory effects on the aggregation of differently charged nanoplastics and their interactions with bacterial membranes. The findings show that EPS forms micelle-like structures driven by hydrophobic and electrostatic interactions, and different components of EPS can promote or suppress its assembly depending on their hydrophobicity and charge. EPS can reduce the adsorption of hydrophobic nanoplastics and alleviate their aggregation through electrostatic repulsion. Additionally, EPS can modulate the binding interactions between nanoplastics and bacterial membranes by reducing the surface charge.
JOURNAL OF HAZARDOUS MATERIALS
(2023)
Article
Developmental Biology
Donovan A. Christman, Haley N. Curry, Labib Rouhana
Summary: The Kinesin Superfamily Protein 3A (KIF3A) and Kinesin Associated Protein 3 (KAP3) are essential for axonemal assembly and nuclear elongation during spermiogenesis in Schmidtea mediterranea. disruption of their expression leads to loss of spermatozoa and accumulation of unelongated spermatids.
DEVELOPMENTAL BIOLOGY
(2021)
Review
Cell Biology
Makoto Miyata, Robert C. Robinson, Taro Q. P. Uyeda, Yoshihiro Fukumori, Shun-ichi Fukushima, Shin Haruta, Michio Homma, Kazuo Inaba, Masahiro Ito, Chikara Kaito, Kentaro Kato, Tsuyoshi Kenri, Yoshiaki Kinosita, Seiji Kojima, Tohru Minamino, Hiroyuki Mori, Shuichi Nakamura, Daisuke Nakane, Koji Nakayama, Masayoshi Nishiyama, Satoshi Shibata, Katsuya Shimabukuro, Masatada Tamakoshi, Azuma Taoka, Yosuke Tashiro, Isil Tulum, Hirofumi Wada, Ken-ichi Wakabayashi
Article
Multidisciplinary Sciences
Yoshiaki Kinosita, Tsubasa Ishida, Myu Yoshida, Rie Ito, Yusuke Morimoto, Kazuki Goto, Richard M. Berry, Takayuki Nishizaka, Yoshiyuki Sowa
SCIENTIFIC REPORTS
(2020)
Article
Biochemistry & Molecular Biology
Yusuke Morimoto, Keiichi Namba, Tohru Minamino
Article
Biology
Tohru Minamino, Miki Kinoshita, Yusuke V. Morimoto, Keiichi Namba
Summary: The bacterial flagellar protein export machinery consists of an export gate complex and ATPase complex, which utilize H+-driven and Na+-driven engines to export flagellar proteins. The FlgN chaperone can activate the Na+-driven engine when the ATPase complex is non-functional, suggesting a backup mechanism to maintain flagellar function. This proposed mechanism helps to explain how bacteria can construct flagella under conditions of restricted proton motive force.
COMMUNICATIONS BIOLOGY
(2021)
Article
Cell Biology
Isabel Sebastian, Nobuhiko Okura, Bruno M. Humbel, Jun Xu, Idam Hermawan, Chiaki Matsuura, Malgorzata Hall, Chitoshi Takayama, Tetsu Yamashiro, Shuichi Nakamura, Claudia Toma
Summary: This study revealed that Leptospira interrogans cleaves E-cadherin and induces endocytosis, leading to disassembly of epithelial cell apical junctional complexes. Furthermore, bacterial transmigration through the paracellular route is crucial for the dissemination of L. interrogans in the host.
CELLULAR MICROBIOLOGY
(2021)
Article
Immunology
Eitoyo Kokubu, Yuichiro Kikuchi, Kazuko Okamoto-Shibayama, Shuichi Nakamura, Kazuyuki Ishihara
Summary: The study demonstrates that dentilisin plays a role in the crawling-dependent surface spreading of T. denticola by affecting its motility speed and efficiency, as evidenced by the smaller colony area, lower crawling velocity, and reduced crawling efficiency observed in dentilisin-deficient strains compared to wild-type and Msp mutant strains.
MICROBIOLOGY AND IMMUNOLOGY
(2021)
Article
Multidisciplinary Sciences
Tohru Minamino, Yusuke Morimoto, Miki Kinoshita, Keiichi Namba
Summary: The text discusses the mechanism of how the proton motive force (PMF) drives flagellar protein export, revealing a close relationship between the protein transport activity of the export gate complex and changes in external pH and Ay.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Multidisciplinary Sciences
Kenta I. Ito, Shuichi Nakamura, Shoichi Toyabe
Summary: Cooperativity plays a central role in biological regulation, providing robust and highly-sensitive regulation. The bacterial flagellar motor regulates torque autonomously based on the dynamic structure of the stator, with a cooperative mechanism in the assembly dynamics. External load triggers dynamic remodeling of the molecular complex sustaining torque, and non-equilibrium allostery leads to an avalanche of succeeding bindings.
NATURE COMMUNICATIONS
(2021)
Correction
Microbiology
Jun Xu, Nobuo Koizumi, Shuichi Nakamura
FRONTIERS IN MICROBIOLOGY
(2021)
Review
Biochemistry & Molecular Biology
Shuichi Nakamura
Summary: The ability of bacteria to move is crucial for their survival and can be a virulence factor for pathogenic species. This review focuses on the significance of motility, particularly crawling, in liquid and on surfaces, for the causative agent of zoonosis leptospirosis.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2022)
Article
Microbiology
Tohru Minamino, Yusuke Morimoto, Miki Kinoshita, Keiichi Namba
Summary: The flagellar export chaperones, including FlgN, FliS, and FliT, play crucial roles in facilitating the efficient export of essential component proteins for filament formation. Dynamic interactions between these chaperones and the transmembrane export gate protein FlhA are believed to determine the order of substrate export.
FRONTIERS IN MICROBIOLOGY
(2021)
Article
Microbiology
Ryo Nakao, Toshiyuki Masuzawa, Shuichi Nakamura, Nobuo Koizumi
Summary: Leptospira kobayashii, a recently designated species of the genus Leptospira, has a complete genome sequence for strain E30, which consists of two circular chromosomes and two plasmids.
MICROBIOLOGY RESOURCE ANNOUNCEMENTS
(2021)
Article
Multidisciplinary Sciences
Jun Xu, Nobuo Koizumi, Yusuke V. Morimoto, Ryo Ozuru, Toshiyuki Masuzawa, Shuichi Nakamura
Summary: Nucleotide second messengers play crucial roles in signal transduction in various organisms. A study has found that the swimming motility of the soil bacterium Leptospira kobayashii can be rapidly modulated by light stimulation. Through analysis of a loss-of-photoresponsivity mutant, a novel sensory gene was identified, and the light-dependent synthesis of cyclic adenosine monophosphate (cAMP) was elucidated. These findings reveal a new role for cAMP in controlling the flagella-dependent motility of Leptospira and highlight the global distribution of the newly discovered photoactivated cyclase among diverse microbial species.
SCIENTIFIC REPORTS
(2022)
Article
Multidisciplinary Sciences
Hidenori Hashimura, Yusuke Morimoto, Yusei Hirayama, Masahiro Ueda
Summary: Research has found that calcium signaling is involved in mechanosensing during Dictyostelium development, including cell motility and morphogenesis, through different molecular mechanisms.
SCIENTIFIC REPORTS
(2022)