#!/usr/bin/awk -f

/^>/ {
    print
    next
}

{
    gsub(/[Aa]/, "a")
    gsub(/[Gg]/, "A")
    gsub(/a/, "G")

    gsub(/[Cc]/, "c")
    gsub(/[Tt]/, "C")
    gsub(/c/, "T")

    print
}