Two immunologically distinct types of protofilaments can be identified in Natrialba magadii flagella

We examine distribution of flagellins along multicomponent flagellar filaments (FF) and protofilaments (PF) of the haloalkaliphilic archaeon Natrialba magadii using immunogold electron microscopy. A high specific polyclonal antibody raised to one of the flagellin types bound homogeneously to the undissociated FF along the full length. At the same time both uniformly labelled and completely unlabelled PF, outwardly indistinguishable one from another, were observed.

Immunologic distinctiveness of archaebacteria that grow in high salt

The antigenic fingerprints of eight halophilic archaebacteria representing the groups recently outlined by molecular and chemical analyses were determined with calibrated antibody probes. Comparison with the antigenic fingerprints of methanogens encompassing all described families and most genera demonstrated that these two archaebacterial groups are themselves antigenically coherent but immunologically distinct.