Abstract The β -carbonic anhydrases (β -CAs) are widely distributed zinc-metalloenzymes that play essential roles in growth, survival, development and virulence in fungi. The majority of filamentous ascomycetes possess multiple β -CA isoforms among which major and minor forms have been characterized. We examined the catalytic behavior of the two minor β -CAs, CafC and CafD, of Aspergillus fumigatus, and found that both enzymes exhibited low CO2 hydration activities. To understand the structural ...
(UH: University of Havana)+ 6 AuthorsHeinz-J. Steinhoff (University of Osnabrück)
Abstract Sticholysin I (StI) is a toxin produced by the sea anemone Stichodactyla helianthus and belonging to the actinoporins family . Upon binding to sphingomyelin-containing membranes StI forms oligomeric pores, thereby leading to cell death. According to recent controversial experimental evidences, the pore architecture of actinoporins is a debated topic. Here, we investigated the StI topology in membranes by site-directed spin labeling and electron paramagnetic resonance spectroscopy. The r...
Abstract Cryo-electron microscopy (cryo-EM) is becoming a method of choice for describing native conformations of biomolecular complexes at high resolution. The rapid growth of cryo-EM in recent years has created a high demand for automated solutions, both in hardware and software. Flexible fitting of atomic models to three-dimensional (3D) cryo-EM reconstructions by molecular dynamics (MD) simulation is a popular technique but often requires technical expertise in computer simulation. This work...
Abstract Plant cytokinins (CKs) are essential for many central cellular processes and play important roles in the interaction between bacteria and plants. Perception of CK is executed by the CHASE domain in the histidine kinase sensors of a class of two-component regulatory systems. Despite advances in understanding the structural basis for CK perception by the sensor AHK4 in Arabidopsis, the molecular mechanism of CK binding by other sensors is unclear. Here, we report the crystal structure of ...
(CAS: Chinese Academy of Sciences), Qing Chang (SJTU: Shanghai Jiao Tong University)+ 3 AuthorsYan Feng10
Estimated H-index: 10
(SJTU: Shanghai Jiao Tong University)
Abstract Endoglycoceramidases (EGCs) are family 5 glycoside hydrolases that catalyze hydrolysis of the glycosidic linkages between the oligosaccharide and ceramide moieties of glycosphingolipids. Three orthologs of EGCs, each with distinct substrate specificity, have been identified to date, including EGC-I, EGC-II, and EGALC. Although the structures of EGC-I and EGC-II have been reported, the substrate preference mechanism of EGC enzymes remains unclear. Here, we determined the crystal structur...
(CAS: Chinese Academy of Sciences)+ 2 AuthorsXinzheng Zhang24
Estimated H-index: 24
(CAS: Chinese Academy of Sciences)
Abstract The throughput of cryo-electron microscopy (cryo-EM) can be improved by employing a procedure that collects beam-image shift data. However, this procedure inadvertently induces a beam tilt, thus decreasing the resolution of the reconstruction. Here, we report an automatic calibration procedure for correcting the beam tilt and a large unexpected astigmatism in the beam-image shift data collection. In this procedure, the changes of the beam tilt and the astigmatism against the beam shift ...
Abstract In many eukaryotes, kinesin-5 motors are essential for mitosis, and small molecules that inhibit human kinesin-5 disrupt cell division. To investigate whether fungal kinesin-5s could be targets for novel fungicides, we studied kinesin-5 from the pathogenic fungus Ustilago maydis . We used cryo-electron microscopy to determine the microtubule-bound structure of its motor domain with and without the N-terminal extension. The ATP-like conformations of the motor in the presence or absence o...
Abstract Cryo-focussed ion beam (FIB)-milling of biological samples can be used to generate thin electron-transparent slices from cells grown or deposited on EM grids. These so called cryo-lamellae allow high-resolution structural studies of the natural cellular environment by in situ cryo-electron tomography. However, the cryo-lamella workflow is a low-throughput technique and can easily be hindered by technical issues like the bending of the lamellae during the final cryo-FIB-milling steps. Th...
Abstract Giardia intestinalis presents an intriguing endomembrane system, which includes endoplasmic reticulum and peripheral vesicles (PVs). The PVs have previously been considered to be organelles that display early and late endosomal and lysosomal properties. Some of these vesicles accumulate macromolecules ingested by the protozoan and show acid phosphatase activity. It has been previously shown that the parasite releases microvesicles, which contribute to giardiasis pathogenesis; however, t...