6Q63

BT0459

Summary for 6Q63

• Entry DOI: 10.2210/pdb6q63/pdb
• Descriptor: Beta-hexosaminidase, COPPER (II) ION, CALCIUM ION, ... (5 entities in total)
• Functional Keywords: glycoside hydrolase family 20, complex n-glycans, microbiota, bacteroidetes, hydrolase
• Biological source: Bacteroides thetaiotaomicron
• Total number of polymer chains: 3
• Total formula weight: 260719.04

Authors

Basle, A.,Crouch, L.,Bolam, D. (deposition date: 2018-12-10, release date: 2019-05-08, Last modification date: 2024-01-24)

Primary citation

Briliute, J.,Urbanowicz, P.A.,Luis, A.S.,Basle, A.,Paterson, N.,Rebello, O.,Hendel, J.,Ndeh, D.A.,Lowe, E.C.,Martens, E.C.,Spencer, D.I.R.,Bolam, D.N.,Crouch, L.I.
Complex N-glycan breakdown by gut Bacteroides involves an extensive enzymatic apparatus encoded by multiple co-regulated genetic loci.
Nat Microbiol, 4:1571-1581, 2019

PubMed Abstract: Glycans are the major carbon sources available to the human colonic microbiota. Numerous N-glycosylated proteins are found in the human gut, from both dietary and host sources, including immunoglobulins such as IgA that are secreted into the intestine at high levels. Here, we show that many mutualistic gut Bacteroides spp. have the capacity to utilize complex N-glycans (CNGs) as nutrients, including those from immunoglobulins. Detailed mechanistic studies using transcriptomic, biochemical, structural and genetic techniques reveal the pathway employed by Bacteroides thetaiotaomicron (Bt) for CNG degradation. The breakdown process involves an extensive enzymatic apparatus encoded by multiple non-adjacent loci and comprises 19 different carbohydrate-active enzymes from different families, including a CNG-specific endo-glycosidase activity. Furthermore, CNG degradation involves the activity of carbohydrate-active enzymes that have previously been implicated in the degradation of other classes of glycan. This complex and diverse apparatus provides Bt with the capacity to access the myriad different structural variants of CNGs likely to be found in the intestinal niche.

PubMed: 31160824
DOI: 10.1038/s41564-019-0466-x

Experimental method

X-RAY DIFFRACTION (2.44 Å)