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In recent years the evolution of olfactory bulb periglomerular cells, as well as the function of periglomerular cells in olfactory encoding, has attracted increasing attention. Studies of neural information encoding based on the analysis of simulation and modeling have given rise to electrophysiological models of periglomerular cells, which have an important role in the understanding of the biology of these cells. In this review we provide a brief introduction to the anatomy of the olfactory system and the cell types in the olfactory bulb. We elaborate on the latest progress in the study of the heterogeneity of periglomerular cells based on different classification criteria, such as molecular markers, structure, ion channels and action potentials. Then, we discuss the several existing electrophysiological models of periglomerular cells, and we highlight the problems and defects of these models. Finally, considering our present work, we propose a future direction for electrophysiological investigations of periglomerular cells and for the modeling of periglomerular cells and olfactory information encoding.

β-1,3-Glucan-degrading enzymes are widely used in fields such as food processing, plant protection, and breweries. In this work, we identified a glycoside hydrolase (GH) family 157 endo-β-1,3-glucanase (BsGlc157A) from Bacteroides sp. M27 and characterized its biochemical properties, structural model, and antifungal activity. Enzymological characterization indicated that BsGlc157A performs its optimal catalytic activity at pH 6.0 and 40 °C. BsGlc157A adopted the classic (β/α) 8 TIM-barrel structure. Two catalytic residues, the nucleophile (Glu215) and the proton donor (Glu123), were confirmed via structural modeling and sitedirected mutagenesis. Moreover, BsGlc157A hydrolyzed curdlan into a series of oligosaccharides with polymerization degrees 2−5 and exhibited inhibitory effects on the hyphal growth of typical fruit pathogenic fungi (Monilinia fructicola, Alternaria alternata, and Colletotrichum gloeosporioides), thereby illustrating effective biocontrol activity. These results revealed the catalytic properties and the application potential of GH family 157 β-1,3-glucanase, thus providing valuable biochemistry information about the group of carbohydrate-active enzymes.