The nucleotide sequence of a 6 kb fragment encoding the main late prot
eins (p14, p38 and p24) of actinophage VWB was obtained. Sequence comp
arison of the encoded proteins with those filed in databases indicated
that the phage VWB main late proteins were all novel. A search for sp
ecial motifs revealed that p14 (13.3 kDa) has a P-loop sequence common
ly found in ATP- and GTP-binding proteins. This observation might indi
cate that p14 is important for ATP-driven DNA translocation during enc
apsidation of VWB phage DNA into the phage head. Furthermore, the poly
peptide ORF2 (26.9 kDa) has an unusual primary structure consisting of
3 stretches of acidic amino acid residues and a glycine/arginine rich
C-terminal end. From comparison with other proteins including the bac
teriophage T4 prohead core component and from the data of special moti
f analysis the ORF2 gene product is probably involved in prohead core
formation.