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Biochemical and structural characterization of a thermostable Dps protein with His-type ferroxidase centers and outer metal-binding sites.

ABSTRACT: The DNA-binding protein from starved cells (Dps) is found in a wide range of microorganisms, and it has been well characterized. However, little is known about Dps proteins from nonheterocystous filamentous cyanobacteria. In this study, a Dps protein from the thermophilic nonheterocystous filamentous cyanobacterium Thermoleptolyngbya sp. O-77 (TlDps1) was purified and characterized. PAGE and CD analyses of TlDps1 demonstrated that it had higher thermostability than previously reported Dps proteins. X-ray crystallographic analysis revealed that TlDps1 possessed His-type ferroxidase centers within the cavity and unique metal-binding sites located on the surface of the protein, which presumably contributed to its exceedingly high thermostability.

SUBMITTER: Minato T

PROVIDER: S-EPMC7327923 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Biochemical and structural characterization of a thermostable Dps protein with His-type ferroxidase centers and outer metal-binding sites.

Minato Takuo T Teramoto Takamasa T Kakuta Yoshimitsu Y Ogo Seiji S Yoon Ki-Seok KS

FEBS open bio 20200528 7

The DNA-binding protein from starved cells (Dps) is found in a wide range of microorganisms, and it has been well characterized. However, little is known about Dps proteins from nonheterocystous filamentous cyanobacteria. In this study, a Dps protein from the thermophilic nonheterocystous filamentous cyanobacterium Thermoleptolyngbya sp. O-77 (TlDps1) was purified and characterized. PAGE and CD analyses of TlDps1 demonstrated that it had higher thermostability than previously reported Dps protei ...[more]

PMID: 32170832

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