Lipopolysaccharide core region

The **lipopolysaccharide (LPS) core region** refers to the central oligosaccharide portion of lipopolysaccharides found in the outer membrane of most Gram-negative bacteria. The full LPS molecule consists of three main parts: lipid A (the hydrophobic anchor), the **core oligosaccharide** (the nonrepeating sugar chain), and O-antigen polysaccharides. The **core oligosaccharide** itself is subdivided into an *inner* and *outer* core. The inner core typically contains conserved sugars such as 3-deoxy-D-manno-octulosonic acid (Kdo) and heptoses, while the outer core includes more variable hexoses like glucose and galactose[1][2][3][5]. This structural domain plays critical roles in maintaining bacterial cell envelope integrity, protecting against environmental threats including antibiotics, contributing to resistance mechanisms, and facilitating interactions with host cells during infection. While essential for bacterial survival and virulence—especially by enabling evasion from host defenses—the "LPS core region" is not itself considered a conventional therapeutic target such as an enzyme or receptor; rather, enzymes involved in its biosynthesis may be targeted experimentally for antibacterial development[1]. The term “Lipopolysaccharide core region” does not refer to a single protein or molecular entity but rather describes part of a complex carbohydrate structure within Gram-negative bacteria’s cell walls. > “Lipopolysaccharide (LPS) contains three moieties: lipid A...core oligosaccharide...and O-antigen.... Both [inner/outer] regions play important roles in survival and virulence....” [1] > “The enterobacterial ‘outer-core’ consists of an oligosaccharide...with Glc, Gal, GlcN...” [3] Because it is neither an individual gene product nor recognized druggable protein/receptor classically catalogued as targets for small molecules or biologics—and because it represents only part of a larger macromolecule—this entry should be flagged as incorrect if used where specific molecular targets are required. If you need information about specific enzymes that synthesize this structure—such as WaaA/KdtA or WaaB glycosyltransferases—please specify further.

Other names

LPS core regionCore oligosaccharide of lipopolysaccharideLipopolysaccharide inner coreLipopolysaccharide outer core