Recombinant Thermotoga petrophila Translation initiation factor IF-2 (infB), partial

Definition and Background

The compound "Recombinant Thermotoga petrophila Translation initiation factor IF-2 (infB), partial" refers to a recombinant protein product derived from the infB gene of Thermotoga petrophila. This gene encodes two forms of the translation initiation factor IF2 (IF2α and IF2β) through dual translational initiation sites . IF2 is a GTP-binding protein essential for bacterial translation initiation, facilitating the binding of initiator fMet-tRNA to the ribosomal P-site and promoting subunit association . The partial recombinant form likely corresponds to truncated or engineered variants of the full-length IF2 protein, often used in structural or functional studies.

Domain Architecture

• IF2 consists of five structural domains (N-domain, G1, G2, C1, C2) as characterized in Bacillus stearothermophilus .

• The C2 domain is critical for fMet-tRNA binding, while the G2 domain houses the GTPase activity .

• Structural dynamics studies reveal interdomain flexibility, with the G2-G3-C1 regions undergoing reorganization during GTP hydrolysis .

Species-Specific Features

• Thermotoga petrophila IF2 shares conserved features with other bacterial IF2 homologs but exhibits unique adaptations for thermophilic environments .

• Comparative genomics suggest recombination events in Thermotoga species, potentially influencing IF2 evolution .

Recombinant Expression

• The product (CSB-BP015164PYI) is expressed in a baculovirus system and purified to >85% purity (SDS-PAGE) .

• Sequence alignment reveals partial coverage of the 700-amino-acid full-length protein, focusing on functional regions (e.g., G2 and C2 domains) .

Ribosomal Interactions

• IF2 localizes near helices H3, H4, H17, and H18 of 16S rRNA and the thiostrepton region of 23S rRNA, as mapped via tethered nucleases .

• The C2 domain interacts with the peptidyl transferase center during fMet-tRNA positioning .

GTP Hydrolysis and Conformational Changes

• GTP hydrolysis by IF2-G2 is required for ribosome recycling but not subunit docking .

• Mutations in the GTPase domain (e.g., G2) disrupt fMet-tRNA release, highlighting IF2’s role in initiation .

Biotechnological Relevance

• Thermotoga enzymes, including IF2, are studied for thermostable properties applicable in biofuel production (cellulase optimization) and medical diagnostics (SARS-CoV-2 detection) .

Data Tables

Table 2: Functional Domains of IF2