Lipopolysaccharide transport protein A (LptA)

Lipopolysaccharide transport protein A (LptA) is a periplasmic protein featuring a novel fold made up of 16 consecutive antiparallel beta-strands arranged in a twisted beta-jellyroll configuration. LptA participates as part of a bridge in the Lpt machinery, facilitating unidirectional movement of LPS molecules from the inner membrane to the outer membrane in Gram-negative bacteria. It assembles in a head-to-tail fashion to form fibers capable of shuttling LPS and interacts with other Lpt proteins (LptC and LptD) to ensure cell envelope integrity. Loss or mutation of LptA impairs LPS transport, sensitizing bacteria to environmental threats and antibiotics. LptA, together with other Lpt proteins (LptB-G), is indispensable for the survival of Gram-negative bacteria, making the Lpt transporter a highly attractive target for novel antibiotic development, especially amid rising multidrug resistance.

Other names

LptAlipopolysaccharide transport protein ALPS transport protein A

Drugs may inhibit LptA directly or trap LPS during transport, preventing proper cell envelope formation and increasing bacterial permeability