We have characterized the fibergenes of adenovirus type 199 (Ad19p), A
d19a, and Ad37 by sequencing. The fiber genes of Ad19a and Ad37 are id
entical and only five amino acids differ comparing Adl 9a/Ad37 with Ad
19p. Based on the translated sequences we calculated the isoelectrical
points (Ips) and found that the fiber knobs of Ad19p, Ad19a, and Ad37
together with Ad8 display the highest Ips of all so far characterized
. Two regions within the fiber knob with unusually basic characteristi
cs have been identified. Sequence alignments revealed that the corresp
onding regions in other fiber knobs are highly antigenic in pepscan an
alysis and of importance for hemagglutination. Only two positions diff
er in the knobs comparing Ad19a/Ad37 with Ad19p. Hence, either of thes
e or both amino acid residues should be expected to be responsible for
the observed differences in hemagglutination between Ad19p and Ad19a/
Ad37. Moreover, we have found two amino acids (Ala(227) and Lys(252))
that are unique in their respective position in Ad19p, Ad19a, Ad37, an
d Ad8. Three amino acids (Lys,,,, Lys(240), and Asn(251)) are unique i
n their respective position in Ad19a and Ad37, that manifest a tropism
for the genital tract. All five amino acids colocalize within one of
the two basic regions. (C) 1997 Academic Press