ISOLATION AND CHARACTERIZATION OF FLAGELLA AND FLAGELLIN PROTEINS FROM THE THERMOACIDOPHILIC ARCHAEA THERMOPLASMA-VOLCANIUM AND SULFOLOBUS-SHIBATAE

Isolated flagellar filaments of Sulfolobus shibatae were 15 nm in diam eter, and they were composed of two major flagellins which have M(r)s of 31,000 and 33,000 and which stained positively for glycoprotein. Th e flagellar filaments of Thermoplasma volcanium were 12 nm in diameter and were composed of one major flagellin which has an M(r) of 41,000 and which also stained positively for glycoprotein. N-terminal amino a cid sequencing indicated that 18 of the N-terminal 20 amino acid posit ions of the 41-kDa flagellin of T. volcanium were identical to those o f the Methanococcus voltae 31-kDa flagellin. Both flagellins of S. shi batae had identical amino acid sequences for at least 23 of the N-term inal positions. This sequence was least similar to any of the availabl e archaeal flagellin sequences, consistent with the phylogenetic dista nce of S. shibatae from the other archaea studied.