Comparison of the deduced amino acid sequence of guinea pig adenovirus hexon protein with that of other mastadenoviruses

Purpose: We sought to isolate, clone, and determine the nucleic acid sequence of the guinea pig adenovirus (GPAdV) hexon gene. From this, the amino acid sequence of the cloned portion was deduced and compared with a set of mastadenovirus hexons. Methods: The DNA isolated from a histologic section of infected guinea pig lung was subjected to high-fidelity amplification, using degenerate primers complementary to a conserved nucleic acid sequence near the 3' end of the hexon gene of mastadenoviruses and a 5' primer from GenBank accession No. X95630 (GPAdV hexon gene partial sequence). The amplified product was cloned, the nucleic acid sequence was determined, and the amino acid sequence was deduced and compared with the hexon amino acid sequences of 25 mastadenoviruses. Results: The cloned fragment comprised 1,603 base pairs (bp) [approximately 50%]) of the hexon. Of the initial 278 nucleic acids of the clone, 276 were identical with GenBank accession No. X95630, and the deduced amino acid sequences of both were identical. The deduced GPAdV hexon amino acid sequence from the clone aligned with structural regions NT, V1, DE1, and FG1 described for human adenovirus types 2 and 5. The GPAdV hexon had < 50% similarity in amino acid sequence, compared with hexons of 25 other mastadenoviruses. Analysis of regional peptide similarities revealed the GPAdV hexon to be more similar to animal mastadenoviruses and human subgroups A, C and F than to other human subgroups. Conclusions: The cloned portion of the GPAdV hexon contained a sequence nearly identical to that of GenBank accession No. X95630. Compared with the truncated amino acid sequences of human adenovirus types 2 and 5, the deduced GPAdV hexon amino acid sequence was similar in areas structurally conserved, but different in areas associated with type-specific antigenicity.