Lipopolysaccharide transport protein complex B-F-G-C (LptBFGC) (LptBFGC)

The LptBFGC lipopolysaccharide transporter complex is a critical multi-protein assembly located in the inner membrane of Gram-negative bacteria (UniProt, 2024). It belongs to the ATP-binding cassette (ABC) transporter family and is responsible for the first step of moving lipopolysaccharide (LPS) molecules from the inner membrane across the periplasm to the outer membrane (Nature, 2019). The complex consists of the ATPase LptB, the transmembrane proteins LptF and LptG, and the bitopic membrane protein LptC (PubMed, 2020). By utilizing energy from ATP hydrolysis, the complex extracts LPS and pushes it onto a bridge formed by LptA, which eventually leads to the LptDE complex at the outer membrane (Science Advances, 2019). Because LPS is essential for the structural integrity and barrier function of the Gram-negative outer membrane, this complex is a high-priority target for the development of novel antibiotics (Journal of Biological Chemistry, 2021). Disrupting LptBFGC function leads to the accumulation of LPS in the inner membrane and eventual bacterial cell death (Nature Communications, 2018). Experimental drugs like thanatin have been shown to interact with components of this complex, particularly LptC, to inhibit bacterial growth (Science, 2019). This target is particularly relevant for treating multi-drug resistant Gram-negative pathogens such as Pseudomonas aeruginosa and Acinetobacter baumannii (Frontiers in Microbiology, 2022).

Other names

LptB2FGC complexInner membrane lipopolysaccharide transloconLptB-LptF-LptG-LptC complexLipopolysaccharide ABC transporter

Inhibition of the extraction of lipopolysaccharide (LPS) from the inner membrane and its subsequent transport to the outer membrane, disrupting the integrity of the bacterial cell envelope.