Expression and characterization of the thylakoid lumen protease DegP1 from Arabidopsis

Yael Chassin, Einat Kapri-Pardes, Galit Sinvany, Tal Arad, Zach Adam*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

63 Scopus citations


The Arabidopsis genome contains 14 genes encoding the serine protease DegP. Products of four of these genes are located in the chloroplast: three in the thylakoid lumen and one on the stromal side of the membrane. We expressed the gene encoding DegP1 as a His-tagged fusion protein in Escherichia coli, purified the protein by affinity chromatography, and characterized it biochemically. Size-exclusion chromatography suggested that DegP1 eluted from the column as a mixture of monomers and hexamers. Proteolytic activity was characterized using β-casein as a model substrate. DegP1 demonstrated concentration-dependent activity, a pH optimum of 6.0 and increasing activity at elevated temperatures. DegP1 was capable of degrading two lumenal proteins, plastocyanin and OE33, suggesting a role as a general-purpose protease in the thylakoid lumen. The results of this work are discussed in the context of the recent elucidation of the structure of the E. coli homolog and the possible physiological role of the protease in the chloroplast lumen.

Original languageAmerican English
Pages (from-to)857-864
Number of pages8
JournalPlant Physiology
Issue number2
StatePublished - Oct 2002


Dive into the research topics of 'Expression and characterization of the thylakoid lumen protease DegP1 from Arabidopsis'. Together they form a unique fingerprint.

Cite this