Evolution of protease activation and specificity via alpha-2-macroglobulin-mediated covalent capture

Carbohydrate-active enzyme (CAZyme) discovery and engineering via (Ultra)high-throughput screening

Carbohydrate-active enzymes (CAZymes) constitute a diverse set of enzymes that catalyze the assembly, degradation, and modification of carbohydrates. These enzymes have been fashioned into potent, selective catalysts by millennia of evolution, and yet are also highly adaptable and readily evolved in the laboratory. To identify and engineer CAZymes for different purposes, (ultra)high-throughput screening campaigns have been frequently utilized with great success. This review provides an overview of the different approaches taken in screening for CAZymes and how mechanistic understandings of CAZymes can enable new approaches to screening. Within, we also cover how cutting-edge techniques such as microfluidics, advances in computational approaches and synthetic biology, as well as novel assay designs are leading the field towards more informative and effective screening approaches.

Leveraging yeast sequestration to study and engineer posttranslational modification enzymes

Enzymes that catalyze posttranslational modifications (PTMs) of peptides and proteins (PTM-enzymes)-proteases, protein ligases, oxidoreductases, kinases, and other transferases-are foundational to our understanding of health and disease and empower applications in chemical biology, synthetic biology, and biomedicine. To fully harness the potential of PTM-enzymes, there is a critical need to decipher their enzymatic and biological mechanisms, develop molecules that can probe and modulate them, and endow them with improved and novel functions. These objectives are contingent upon implementation of high-throughput functional screens and selections that interrogate large sequence libraries to isolate desired PTM-enzyme properties. This review discusses the principles of Saccharomyces cerevisiae organelle sequestration to study and engineer PTM-enzymes. These include outer membrane sequestration, specifically methods that modify yeast surface display, and cytoplasmic sequestration based on enzyme-mediated transcription activation. Furthermore, we present a detailed discussion of yeast endoplasmic reticulum sequestration for the first time. Where appropriate, we highlight the major features and limitations of different systems, specifically how they can measure and control enzyme catalytic efficiencies. Taken together, yeast-based high-throughput sequestration approaches significantly lower the barrier to understanding how PTM-enzymes function and how to reprogram them.

Proteomics Clustering Research of ITRAQ Markers in Plasma of AIDS Patients with Different Chinese Medicine Syndromes

Background

We aimed to distinguish the different Chinese medicine (CM) syndromes of acquired immune deficiency syndrome (AIDS) patients at the proteomics level.

Methods

We collected AIDS patients diagnosed with different CM syndromes from Weishi County, Kaifeng City, Henan Province, China, including Qi-deficiency syndrome (named QD group) and dampness-heat syndrome (named DH group). Healthy people were collected as controls from Weishi County, Kaifeng city, Henan Province, China. The plasma from three groups were labeled with ITRAQ, LC/MC was used for protein quantitative analysis. Finally, sequence search and cluster analysis were performed.

Results

Overall, 27 different proteins were found. Three proteins were up-regulated and 2 proteins down-regulated in the QD group, 11 proteins up-regulated and 13 proteins down-regulated in the DH group. Compared with DH group, there were 7 different proteins in QD group, among which 5 proteins were down-regulated and 2 proteins were up-regulated. When the target protein of DH group was up-regulated, the protein of HC group was down-regulated correspondingly.

Conclusion

The significance analysis and clustering of protein results showed that DH group was significantly different from QD group and HC group at the protein level (P<0.05). However, the QD group could not be effectively distinguished from the HC group. AAT, PF4, C-reactive protein and c4bp may be used as potential biomarkers in DH group. Mass spectrometry based on feature selection can be used to classify different CM syndromes.