In a system of purified components , binding of __SP__ __NODE__ protein and __SP__ __NODE__ protein and __SP__ __NODE__ protein containing a carboxy terminal domain and a linker domain and a N terminal domain is the same as binding of mutant __SP__ __NODE__ protein ( X54R X55R ) and __SP__ __NODE__ protein and __SP__ __NODE__ protein containing a carboxy terminal domain and a linker domain and a N terminal domain .