8WWF

Crystal structure of (R)-DHPS dehydrogenase HpsO from Ruegeria pomeroyi DSS-3

Summary for 8WWF

• Entry DOI: 10.2210/pdb8wwf/pdb
• Descriptor: (R)-DHPS dehydrogenase HpsO (2 entities in total)
• Functional Keywords: nad-dependent, oxidoreductase
• Biological source: Ruegeria pomeroyi DSS-3
• Total number of polymer chains: 4
• Total formula weight: 105851.02

Authors

Liu, L.,Tang, K. (deposition date: 2023-10-25, release date: 2024-09-04, Last modification date: 2024-09-11)

Primary citation

Liu, L.,Gao, X.,Dong, C.,Wang, H.,Chen, X.,Ma, X.,Liu, S.,Chen, Q.,Lin, D.,Jiao, N.,Tang, K.
Enantioselective transformation of phytoplankton-derived dihydroxypropanesulfonate by marine bacteria.
Isme J, 18:-, 2024

PubMed Abstract: Chirality, a fundamental property of matter, is often overlooked in the studies of marine organic matter cycles. Dihydroxypropanesulfonate (DHPS), a globally abundant organosulfur compound, serves as an ecologically important currency for nutrient and energy transfer from phytoplankton to bacteria in the ocean. However, the chirality of DHPS in nature and its transformation remain unclear. Here, we developed a novel approach using chiral phosphorus-reagent labeling to separate DHPS enantiomers. Our findings demonstrated that at least one enantiomer of DHPS is present in marine diatoms and coccolithophores, and that both enantiomers are widespread in marine environments. A novel chiral-selective DHPS catabolic pathway was identified in marine Roseobacteraceae strains, where HpsO and HpsP dehydrogenases at the gateway to DHPS catabolism act specifically on R-DHPS and S-DHPS, respectively. R-DHPS is also a substrate for the dehydrogenase HpsN. All three dehydrogenases generate stable hydrogen bonds between the chirality-center hydroxyls of DHPS and highly conserved residues, and HpsP also form coordinate-covalent bonds between the chirality-center hydroxyls and Zn2+, which determines the mechanistic basis of strict stereoselectivity. We further illustrated the role of enzymatic promiscuity in the evolution of DHPS metabolism in Roseobacteraceae and SAR11. This study provides the first evidence of chirality's involvement in phytoplankton-bacteria metabolic currencies, opening a new avenue for understanding the ocean organosulfur cycle.

PubMed: 38709871
DOI: 10.1093/ismejo/wrae084

Experimental method

X-RAY DIFFRACTION (1.7 Å)