PAQR3 controls autophagy by integrating AMPK signaling to enhance ATG14L-associated PI3K activity.

The Beclin1-VPS34 complex is recognized as a central node in regulating autophagy via interacting with diverse molecules such as ATG14L for autophagy initiation and UVRAG for autophagosome maturation. However, the underlying molecular mechanism that coordinates the timely activation of VPS34 complex is poorly understood. Here, we identify that PAQR3 governs the preferential formation and activation of ATG14L-linked VPS34 complex for autophagy initiation via two levels of regulation.

Production of a bioactive sweetener steviolbioside via specific hydrolyzing ester linkage of stevioside with a β-galactosidase.

A β-galactosidase from Kluyveromyces lactis was found to specifically catalyze hydrolysis of the glycosyl ester linkage of stevioside to yield steviolbioside, a rare sweetener that also exists in Stevia rebaudiana leaves. In a packed bed reactor, a reaction coupling separation was realized and a production yield of steviolbioside reached 90% in 6 h. The hydrolysis product steviolbioside presented higher cytoxicity on human normal cells (hepatocytes cell L02 and intestinal epithelial cell T84) than stevioside did.

Enzymatic transformation of stevioside using a β-galactosidase from Sulfolobus sp.

Enzymatic hydrolysis and transgalactosylation of stevioside (St) were investigated using a β-galactosidase from Sulfolobus sp. The hydrolysis yielded steviol as the main final product. Under the optimal transgalactosylation conditions, the highest conversion of stevioside was 87.

Crystal structure of di-μ-iodido-bis-{[1,3-bis-(2,6-diiso-propyl-phen-yl)imidazol-2-yl-idene]lithium}.

In the title binuclear complex, [Li2(C27H36N2)2I2], the unique Li(I) cation is coordinated by two iodide anions and one yl-idene C atom from a 1,3-bis-(2,6-diiso-propyl-phen-yl)imidazol-2-yl-idene ligand in a distorted trigonal-planar geometry. The two symmetry-related iodide anions bridge two Li(I) cations, forming an inversion dimer in which the Li2I2 plane is nearly perpendicular to the imidazol-2-yl-idene ring, with a dihedral angle of 85.5 (3)°.

Nonthermal effect of microwave irradiation in nonaqueous enzymatic esterification.

Microwave has nonthermal effects on enzymatic reactions, mainly caused by the polarities of the solvents and substrates. In this experiment, a model reaction with caprylic acid and butanol that was catalyzed by lipase from Mucor miehei in alkanes or arenes was employed to investigate the nonthermal effect in nonaqueous enzymatic esterification. With the comparison of the esterification carried by conventional heating and consecutive microwave irradiation, the positive nonthermal effect on the initial reaction rates was found substrate concentration-dependent and could be vanished ostensibly when the substrate concentration was over 2.