Structures of three MORN repeat proteins and a re-evaluation of the proposed lipid-binding properties of MORN repeats
Fig 2
Recombinant TbMORN1 co-purifies with PE and increases E. coli PE levels.
Negative ion mode survey scan (600–900 m/z) of lipid extracts from the indicated conditions. (A,B) Lipid extracts from purified recombinant TbMORN1(1–15) (A) and TbMORN1(10–15) (B). A large amount of PE co-purified with TbMORN1(1–15) but very little was associated with TbMORN1(10–15). (C,D) Lipid extracts from E. coli cells expressing the indicated constructs. (C) Cells expressing TbMORN1(1–15) had elevated PE levels. (D) Cells expressing TbMORN1(10–15) showed no changes to cellular lipid ratios compared to wild-type (empty vector control). In all cases, phospholipid identity was confirmed by daughter fragmentation and reported here. Schematics of the recombinant TbMORN1 constructs are shown above the traces.