Analysis of Bacterial Single-Stranded DNA-Binding Protein

Our experts have a keen interest in the study of liquid-liquid and liquid-solid phase transitions in bacterial cells. We have cutting-edge super-resolution imaging or infinite diffraction microscopy apparently combined with single molecule trafficking methods, and computer analysis platforms to analyze key microbial biomolecular condensates undergoing LLPS, as well as the formation and organization of biomolecular condensates within the intracellular space. Here, CD BioSciences is committed to analyzing intrinsically disordered bacterial single-stranded DNA-binding protein (SSB).

Introduction of Bacterial Single-Stranded DNA-Binding Protein

Bacterial SSBs are essential for genome replication and maintenance and have been well-studied in eubacteria, particularly in E. coli. SSBs share a conserved ssDNA binding domain, a less conserved intrinsically disordered junction, and a highly conserved C-terminal peptide (CTP) motif that mediates multiple protein-protein interactions with DNA metabolizing proteins. SSB are multi-structured and partially disordered. It has been shown that at ionic strengths corresponding to assumed concentrations of anions and cations in bacterial cells, SSB proteins form regular spherical droplets, similar to the liquid-liquid phase separation (LLPS) formation of liquid condensates.

Fig. 1. Proposed model for the in vivo role of SSB LLPS. (Harami G M, et al., 2020)

Customized Services

SSB plays an important role in repair, recombination, and replication in all organisms as a highly conserved pleiotropic regulatory protein. Eukaryotic SSB is regulated by the phosphorylation of serine and threonine residues. Our technical team is developing an E. coli model to analyze SSB undergoing LLPS and forming sticky liquid protein droplets under physiologically relevant ionic conditions and protein concentrations in the presence and absence of molecular crowding.

CD BioSciences provides professional services to analyze the structural dynamics and biochemical functions of the intrinsically disordered SSB in bacteria. Our services include:

• Characterization of SSB LLPS in Vitro
  We provide comprehensive SSB LLPS bioinformatics analysis using a variety of dedicated sequence-based prediction methods to analyze the LLPS propensity of E. coli SSB, particularly its intrinsically disordered junction region.
  In addition, we can combine turbidity measurements and fluorescence imaging to characterize the liquid-like droplets formed by SSB in vitro. The fluorescence recovery after photobleaching (FRAP) technique is used to measure the material properties of SSB droplets. Genetic and fluorescence studies are used to analyze the ability of SSB droplets to undergo phase separation.
  
• Characterization of SSB Condensates in Cytoplasmic Extracts
  We provide fallout fluorescence microscopy to analyze SSB condensate formation in E. coli cell extracts to further assess the potential for SSB phase separation to occur in the cellular environment.
• Development of Bacterial SSB Inhibitors
  The biochemical and metabolic characteristics of SSB make this protein an attractive target for the development of antimicrobial compounds. Our experts are committed to developing SSB as an important target for antimicrobial chemotherapy and exploring SSB inhibitors.

CD BioSciences offers a simple modular biomolecular platform to characterize the LLPS of intrinsically disordered SSB. We aim to analyze the molecular interactions that drive SSB assembly in bacteria and help our customers understand the organizational role of SSBs in genome maintenance. If you have any special requirements for our services, please feel free to contact us.