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B-cell maturation antigen (BCMA) fused at the C-terminus to the Fc portion of human IgG1 (BCMA-Fc) blocks B-cell activating factor (BAFF) and proliferation-inducing ligand (APRIL)-mediated B-cell activation, leading to immune disorders. The fusion protein has been cloned and produced by several engineering cell lines. To reduce cost and enhance production, we attempted to express recombinant human BCMA-Fc (rhBCMA-Fc) in Pichia pastoris under the control of the AOX1 methanol-inducible promoter. To produce the target protein with uniform molecular weight and reduced immunogenicity, we mutated two predicted N-linked glycosylation sites. The secretory yield was improved by codon optimization of the target gene sequence. After fed-batch fermentation under optimized conditions, the highest yield (207 mg/L) of rhBCMA-Fc was obtained with high productivity (3.45 mg/L/h). The purified functional rhBCMA-Fc possessed high-binding affinity to APRIL and dose-dependent inhibition of APRIL-induced proliferative activity in vitro through three-step purification. Thus, this yeast-derived expression method could be a low-cost and effective alternative to the production of rhBCMA-Fc in mammalian cell lines. [ABSTRACT FROM AUTHOR]

Phosphorus (P) in hydrolysed urine can be recovered through struvite formation. In the present study, batch experiments were conducted to investigate the effects of contact to the atmosphere (i.e. open and closed) and dilution [Vurine/(Vurine+Vwater)] (i.e. 100%, 50% and 25%) on P recovery from fresh urine through struvite formation with the addition of magnesium chloride (molar ratios of Mg/P=1.3 and 2.0) after 32 d of storage. The P loss mainly occurred during the initial stages of precipitation with calcium and magnesium (5 d). The precipitates formed at the bottom of the jars were identified by X-ray diffraction to be struvite, hydroxyapatite and calcite. The results showed that the P recovery efficiency from urine solutions in open jars was lower than that in closed jars. It caused significant ammonia volatilization in open jars, resulting in higher nitrogen loss, lower pH values and lower supersaturation. The P recovery efficiency decreased with dilution, which is related to lower pH and lower supersaturation resulting from water dilution. An increase in the Mg/P ratio from 1.3 to 2.0 enhanced P recovery to some extent in urine solutions with different dilutions. The largest P recovery efficiency was 93.7% and 97.3% at an Mg/P ratio of 1.3 and 2.0 for the 100% urine solutions in closed jars, respectively. Scanning electron microscopy revealed smaller struvite particle sizes at lower dilutions (100% and 50% urine) compared with higher dilutions (25% urine). [ABSTRACT FROM PUBLISHER]

Abstract: Solubility data and the density of equilibrium liquid phase for the ternary system m-nitrobenzoic acid+ p-nitrobenzoic acid+acetone were determined at 283.1K and 313.1K, and the phase diagrams of the system were constructed. Two solid phases, pure solid m-nitrobenzoic acid and p-nitrobenzoic acid are confirmed by the Schreinemaker''s wet residue method. The crystallization regions of m-nitrobenzoic acid and p-nitrobenzoic acid increase as the temperature decreases. At the same temperature, the crystallization region of p-nitrobenzoic acid is larger than that of m-nitrobenzoic acid. [Copyright &y& Elsevier]