Anti-SYN2 (aa 348-448) polyclonal antibody

To investigate the temporal-spatial distribution of picophytoplankton in relation to different water masses in the northern East China Sea (ECS), picophytoplankton abundance and biomass were investigated using flow cytometry with environmental factors in May, August, and November 2010 and February 2012. Five picophytoplankton populations, including Prochlorococcus (Pro), low and high orange fluorescence Synechococcus (Syn1 and Syn2), and small and large sized picoeukaryotes (SPEuks and LPEuks) were discriminated, and each group responded differently to the water mass distribution. Synl was the predominant group in the picophytoplankton abundance in all seasons, indicating ecological importance as a primary producer in the northern ECS. LPEuks was a minor group in terms of the abundance but they contributed significantly to the total picophytoplankton carbon biomass in spring and winter due to their larger size among picophytoplankton groups. Two geographical groups were distinguished in the northern ECS. One group (including Synl and LPEuks) was distributed mainly in the western area affected by the Changjiang discharge and Chinese coastal waters, and the other group (including Pro, Syn2, and SPEuks) dominated picophytoplankton abundance in the eastern area characterized by the Kuroshio intrusion. Pro was detected in the eastern side of the study area during each survey, except in May, indicating the possible effect of the low Kuroshio intrusion on the northern ECS in late spring. This study shows that the distributions of these picophytoplanktons are strongly influenced by the seasonal fluctuations of the Changjiang discharge and Kuroshio intrusion in the northern ECS. (C) 2014 Elsevier Ltd. All rights reserved.

Affinity chromatography is generally regarded as a powerful tool allowing the single step purification of recombinant proteins with high purity and yields. However, for most protein products, affinity purification methods for industrial applications are not readily available, mainly due to the lack of specific and robust natural counterparts that could function as affinity ligands. In this study, we explored the applicability of nanobody-based peptide-tag immunorecognition systems as a platform for affinity chromatography. Two typical nanobodies (BC2-nb and Syn2-nb) that are capable of recognizing specifically a particular peptide-tag, were prepared through prokaryotic expression and proved to be able to bind with nanomolar affinity to their cognate tag fused to enhanced green fluorescent protein (eGFP). Through an epoxy-based immobilization reaction, the two nanobodies were coupled on a Sepharose CL-6B matrix under the same conditions. The remaining antigen binding activity of the immobilized BC2-nb and Syn2-nb was determined to be 83.1% and 42.9%, yielding the resins with the dynamic binding capacity (DBC) of 21.4 mg/mL and 5.9 mg/mL, respectively. The immobilized affinity ligands exhibited high binding specificity towards their respective target peptides, yielding a product purity above 90% directly from crude bacterial lysates in one single chromatographic step. However, for the both affinity complexes, desorption has been found difficult, and effective recovery of the bound products could be only achieved with competitive elution or after employing harsh conditions such as 10 mM NaOH solution, which will compromise the reuse cycles of the affinity resins. This study shows the potential of nanobody-based affinity chromatography for efficient purification of recombinant proteins especially from complex feedstocks and reveals the primary issues to be addressed to develop a successful application. (C) 2020 Elsevier B.V. All rights reserved.