High-performance liquid chromatography–inductively coupled plasma mass spectrometry (HPLC-ICP-MS) is becoming a significant complementary technique of HPLC–molecular mass spectrometry for proteins and peptides quantification. However, the naturally occurring heteroelements inside proteins and peptides, such as sulfur, phosphor, and selenium, are not sensitive enough in ICP-MS for low-abundance proteins and peptides, due to their low ionization efficiency or polyatomic spectral interference. In order to make the low-abundance proteins and peptides “visible” by HPLC-ICP-MS, a foreign elemental tag can be employed. The foreign elemental tags are highly sensitive in ICP-MS and almost absent in common biological matrices, which leads to significantly low limits of detection. This review summarizes the major applications of elemental tags in combination with HPLC-ICP-MS detection. The organic mercury tags, iodine tags, ferrocene tags, and macrocyclic metal chelate complex tags are discussed in detail. The recent development of HPLC-ICP-MS in combination with elemental tags demonstrates the great potential in sensitive and accurate proteins and peptides quantification.

Soil bacterial communities play a crucial role in the functioning of estuarine wetlands. Investigating the structure and function of these communities across various wetland types, along with the key factors influencing them, is essential for understanding the relationship between bacteria and wetland ecosystems. The Liaohe Estuary Wetland formed this study’s research area, and soil samples from four distinct wetland types were utilized: suaeda wetlands, reed wetlands, pond returning wetlands, and tidal flat wetlands. The structure and function of the soil bacterial communities were examined using Illumina MiSeq high-throughput sequencing technology in conjunction with the PICRUSt analysis method. The results indicate that different wetland types significantly affect the physical and chemical properties of soil, as well as the structure and function of bacterial communities. The abundance and diversity of soil bacterial communities were highest in the suaeda wetland and lowest in the tidal flat wetland. The dominant bacterial phyla identified were Proteobacteria and Bacteroidota. Furthermore, the dominant bacterial genera identified included RSA9, SZUA_442, and SP4260. The primary functional pathways associated with the bacterial communities involved the biosynthesis of valine, leucine, and isoleucine, as well as lipoic acid metabolism, which are crucial for the carbon and nitrogen cycles. This study enhances our understanding of the mutual feedback between river estuary wetland ecosystems and environmental changes, providing a theoretical foundation for the protection and management of wetlands.

In this study, a laboratory-scale biodegradation, electron transfer based on sulfur metabolism integrated (BESI^®) process was used on the treatment of petrochemical reverse osmosis concentrate (ROC). ROC is a type of saline wastewater with low biodegradability. In the operational days, the chemical oxygen demand (COD) and total organic carbon removal efficiencies on average were 79.18 and 79.39%, respectively. The removal efficiencies of ammonia nitrogen and total nitrogen on average were 79.84 and 83.60%, respectively. High-throughput pyrosequencing was applied on the analysis of the microbial community in activated sludge and biofilm samples. The functional phylotypes sulfate-reducing bacteria (SRB) were detected in anaerobic reactor, and they participated in the COD removal and sulfate reduction. The genera Hyphomicrobium, Azoarcus, Thauera, Paracoccus, and Nitrospira were detected in the BESI^® process. These genera contributed to the nitrogen transformation, and they played different roles in each reactor of the integrated process.