Publications by authors named "Dongming Zhi"

2 Publications

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A new constraint on the antiquity of ancient haloalkaliphilic green algae that flourished in a ca. 300 Ma Paleozoic lake.

Geobiology 2021 03 16;19(2):147-161. Epub 2020 Dec 16.

Department of Earth and Planetary Sciences, University of California, Riverside, CA, USA.

It is established that green algae and land plants progressively colonized freshwater and terrestrial habitats throughout the Paleozoic Era, but little is known about the ecology of Paleozoic saline lakes. Here, we report lipid biomarker and petrographic evidence for the occurrence of a green alga as a major primary producer in a late Paleozoic alkaline lake (Fengcheng Formation; 309-292 Ma). A persistently saline and alkaline lacustrine setting is supported by mineralogical and lipid biomarker evidence alongside extremely enriched δ N values (+16 to +24‰) for the lake depocenter. The prominence of C and C steroids, co-occurring with abundant carotene-derived accessory pigment markers in these ancient rocks, is suggestive of prolific primary production and elevated source inputs from haloalkaliphilic green algae. The high C /C -sterane ratios (0.78-1.29) are significantly higher than the typical marine value reported for late Paleozoic rocks (<0.5) and thus are associated with certain groups of chlorophytes. Adaptation to such extreme lacustrine environments, aided by enhanced biosynthesis of certain cell membrane lipids, likely played an important role in the evolution and physiological development of ancient green algae.
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http://dx.doi.org/10.1111/gbi.12423DOI Listing
March 2021

The N-terminal 1-55 residues domain of pyruvate dehydrogenase from Escherichia coli assembles as a dimer in solution.

Protein Eng Des Sel 2019 12;32(6):271-276

College of Chemistry and Pharmacy, Northwest A&F University, Yangling, China.

The pyruvate dehydrogenase complex (PDHc) from Escherichia coli is a large protein complex consisting of multiple copies of the pyruvate dehydrogenase (E1ec), dihydrolipoamide acetyltransferase (E2ec) and dihydrolipoamide dehydrogenase (E3ec). The N-terminal domain (NTD, residues 1-55) of E1ec plays a critical role in the interaction between E1ec and E2ec and the whole PDHc activity. Using circular dichroism, size-exclusion chromatography and dynamic light scattering spectroscopy, we show that the NTD of E1ec presents dimeric assembly under physiological condition. Pull-down and isothermal titration calorimetry binding assays revealed that the E2ec peripheral subunit-binding domain (PSBD) forms a very stable complex with the NTD, indicating the isolated NTD functionally interacts with PSBD and the truncated E1ec (E1ec∆NTD) does not interact with PSBD. These findings are important to understand the mechanism of PDHc and other thiamine-based multi-component enzymes.
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http://dx.doi.org/10.1093/protein/gzz044DOI Listing
December 2019