
대장균에서 브라운 지단백질은 펩티도글리칸 전구체에 선행적으로 결합되지 않으며, 펩티도글리칸 확장 과정에 독립적으로 결합된다. 또한 결합된 브라운 지단백질은 L,D-트랜스펩티다제에 의해 펩티도글리칸 사슬 간에 역동적으로 이동한다.


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Peptidoglycan (PG) is a giant macromolecule that completely surrounds bacterial cells and prevents lysis in hypo-osmotic environments. This net-like macromolecule is made of glycan strands linked to each other by two types of transpeptidases that form either 4→3 (PBPs) or 3→3 (LDTs) cross-links. Previously, we devised a heavy isotope-based PG full labeling method coupled to mass spectrometry to determine the mode of insertion of new-subunits into the expanding PG network ([Atze et al., 2022][1]). We showed that PG polymerization operates according to different modes for the formation of the septum and of the lateral cell walls, as well as for bacterial growth in the presence or absence of β-lactams in engineered strains that can exclusively rely on LDTs for PG cross-linking when drugs are present. Here, we apply our method to the resolution of the kinetics of the reactions leading to the covalent tethering of the Braun lipoprotein (Lpp) to PG and the subsequent hydrolysis of that same covalent link. We find that Lpp and disaccharide-peptide subunits are independently incorporated into the expanding lateral cell walls. Newly synthesized septum PG appears to contain small amounts of tethered Lpp. LDTs did mediate intense shuffling of Lpp between PG stems leading to a dynamic equilibrium between the PG-tethered and free forms of Lpp.

### Competing Interest Statement

The authors have declared no competing interest.

 [1]: #ref-3

Peptidoglycan-tethered and free forms of the Braun lipoprotein are in dynamic equilibrium in Escherichia coli

대장균에서-펩티도글리칸-결합-및-자유-형태의-브라운-지단백질이-역동적-평형-상태에-있음


대장균에서 펩티도글리칸 결합 및 자유 형태의 브라운 지단백질이 역동적 평형 상태에 있음
