Identification and functional analysis of histone 1.2-like in red sea bream (Pagrus major).

Histone H1 acts as an essential chromatin component and participates in the formation of higher chromatin structures together with core histones. In addition, H1 also has important functions in physiological processes such as gene expression regulation, DNA repair, and the immune response. In this study, the histone homologous protein Pm-H1.2-like was identified from the transcriptome database of Pagrus major we studied previously. Conservatism of evolution was investigated by sequence alignment and phylogenetic analysis. Transcripts of Pm-H1.2-like were detected in P. major tissues. The highest expression level was found in gill and skin tissues. Consistent with the data from the transcriptome database, we observed that the expression of Pm-H1.2-like was rapidly induced in nonspecific cytotoxic cells (NCCs) infected with inactivated Vibrio anguillarum. Gene silencing of Pm-H1.2-like by RNAi significantly suppressed the expression of NK-lysin and GZMB in NCCs at 12 h after pathogen stimulation, but had no significant effect on IFN-γ expression. Next, we obtained the fusion proteins rPm-H1.2-like and rPm-H1.2-like (36-80) through prokaryotic expression. ELISA showed that rPm-H1.2-like bound to oligonucleotide (ODN) in a concentration-dependent manner, while no binding activity of rPm-H1.2-like (36-80) with ODN was observed. This study confirmed that Pm-H1.2-like actively participates in the immune response of NCCs to bacterial infection, deepening the understanding of the immune features of histone H1 in fish.

Investigation of COVID-19 Impact on the Food and Beverages Industry: China and India Perspective.

The sudden breakout of coronavirus disease (COVID-19) rapidly spread across the globe, leaving no country behind in being affected by the global pandemic in the year 2019-20. As COVID-19 commenced, within months two major Asian giants initiated the norms of social distancing and lockdowns in their societies. The indiscriminate nature of the current pandemic has not only impacted the health and quality of life of people but has also disrupted the global economy, supply chains, and countries all over the world. In food and beverage manufacturing industries, the unanticipated disruption has encumbered its lock on the global food supply chain and service sector as major cities shut down for several months in China and India. Human existence is dependent upon food, which renders energy for activity, growth, and all functions of the body. Although both China and India have shown eminent response to tackle the ongoing pandemic, the food supply chain remains vastly exposed to significant COVID-19 risks. This research primarily investigates the ongoing COVID-19 scenario in two major economies (China and India), delivering insight into the pandemic's impact within the food and beverage manufacturing sectors, and explores the policies adopted and strategies undertaken for sustainability in food supply chains.

Visual detection of tropomyosin, a major shrimp allergenic protein using gold nanoparticles (AuNPs)-assisted colorimetric aptasensor.

A gold nanoparticle-based label-free colorimetric assay was developed to detect the shrimp allergenic protein tropomyosin (TM), an important biomarker responsible for severe clinical reactivity to shellfish. In a gold nanoparticles (AuNPs)-tropomyosin-binding aptamer (TMBA) complex, the aptamer adsorbs onto the surface of AuNPs and dissociates in the presence of TM. In addition, AuNPs tend to aggregate in the presence of ionic salt, revealing a color change (i.e., wine-red to purple/blue) with a shift in the maximum absorption peak from 520 nm. In the presence of specific binding TM, the aptamer folds into a tertiary structure where it more efficiently stabilizes AuNPs toward the salt-induced aggregation with a hypsochromic shift in the absorption spectra compared to the stabilized AuNPs by aptamer alone. Based on the aggregation and sensitive spectral transformation principle, the AuNPs-based colorimetric aptasensor was successfully applied to detect TM with a range of 10-200 nmol/L and a low detection limit of 40 nmol/L in water samples. The reliability, selectivity, and sensitivity of the aptasensor was then tested with food samples spiked with TM. The observed detection limit was as low as 70 nmol/L in shrimp, 90 nmol/L in tofu, and 80 nmol/L in eggs, respectively. We anticipate the proposed AuNPs-based colorimetric aptasensor assay possesses a high potential for the easy and efficient visual colorimetric detection of TM. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-020-00085-5.