Structural basis of promoter recognition by Staphylococcus aureus RNA polymerase.

Bacterial RNAP needs to form holoenzyme with σ factors to initiate transcription. While Staphylococcus aureus σ controls housekeeping functions, S. aureus σ regulates virulence, biofilm formation, persistence, cell internalization, membrane transport, and antimicrobial resistance.

Structural insights into the N-terminal APHB domain of HrpA: mediating canonical and i-motif recognition.

RNA helicases function as versatile enzymes primarily responsible for remodeling RNA secondary structures and organizing ribonucleoprotein complexes. In our study, we conducted a systematic analysis of the helicase-related activities of Escherichia coli HrpA and presented the structures of both its apo form and its complex bound with both conventional and non-canonical DNAs. Our findings reveal that HrpA exhibits NTP hydrolysis activity and binds to ssDNA and ssRNA in distinct sequence-dependent manners.

Biochemical and functional characterization of an exonuclease from Chaetomium thermophilum.

Exonucleases are often found associated with polymerase or helicase domains in the same enzyme or can function as autonomous entities to maintain genome stability. Here, we uncovered Chaetomium thermophilum RecQ family proteins that also have exonuclease activity in addition to their main helicase function. The novel exonuclease activity is separate from the helical core domain and coexists with the latter two enzymatic activities on the same polypeptide.

iTRAQ-based quantitative proteome revealed metabolic changes of Flammulina velutipes mycelia in response to cold stress.

Unlabelled: Temperature is one of the pivotal factors influencing mycelium growth and fruit-body formation of Flammulina velutipes. To gain insights into hyphae growth and fruit-body formation events and facilitate the identification of potential stage-specific biomarker candidates, we investigated the proteome response of F. velutipes mycelia to cold stresses using iTRAQ-coupled two-dimensional liquid chromatography tandem mass spectrometry (2D LC-MS/MS) technique.