Intracellular Ca(2+) oscillations generated via the extracellular Ca(2+)-sensing receptor (CaSR) in response to extracellular Ca(2+) or L-phenylalanine: Impact of the highly conservative mutation Ser170Thr

One-step production of functional branched oligoglucosides with coupled fermentation of Pichia pastoris GS115 and Sclerotium rolfsii WSH-G01

Endo-β-1,3-glucanase with high specific activity is a prerequisite for enzymatic preparation of valuable β-oligoglucosides. Heterologous expression in Pichia pastoris GS115 with error-prone PCR technology was implemented, and the mutant strain 7 N12 was obtained. The mutant endo-β-1,3-glucanase showed efficient specific activities for degrading curdlan (366 U mg^-1) and scleroglucan (274.5 U mg^-1). Thereafter, one-step production of functional branched oligoglucosides was established with coupled fermentation of Pichia pastoris and Sclerotium rolfsii. During the fermentation process, the endo-β-1,3-glucanase secreted by Pichia pastoris GS115 can efficiently hydrolyse scleroglucan metabolized by Sclerotium rolfsii WSH-G01. The maximum yields of β-oligoglucosides in the shake flasks and 7-L bioreactor reached 1.73 g L^-1 and 12.71 g L^-1, respectively, with polymerization degrees of 2-17. The successful implementation of heterologous expression with error-prone PCR and the coupled fermentation simplified the multi-step enzymatic β-oligoglucoside preparation procedures, which makes it a potential strategy for industrial production of functional oligosaccharides.

Cortex phellodendri Extract Relaxes Airway Smooth Muscle

Cortex phellodendri is used to reduce fever and remove dampness and toxin. Berberine is an active ingredient of C. phellodendri. Berberine from Argemone ochroleuca can relax airway smooth muscle (ASM); however, whether the nonberberine component of C. phellodendri has similar relaxant action was unclear. An n-butyl alcohol extract of C. phellodendri (NBAECP, nonberberine component) was prepared, which completely inhibits high K⁺- and acetylcholine- (ACH-) induced precontraction of airway smooth muscle in tracheal rings and lung slices from control and asthmatic mice, respectively. The contraction induced by high K⁺ was also blocked by nifedipine, a selective blocker of L-type Ca²⁺ channels. The ACH-induced contraction was partially inhibited by nifedipine and pyrazole 3, an inhibitor of TRPC3 and STIM/Orai channels. Taken together, our data demonstrate that NBAECP can relax ASM by inhibiting L-type Ca²⁺ channels and TRPC3 and/or STIM/Orai channels, suggesting that NBAECP could be developed to a new drug for relieving bronchospasm.