hmmfetch: command not found

Have You tried accessing the binary with the full path?

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/hmmfetch - from package: hmmer

You may install the required package with command apt-get install {package}
Error in other languages:
hmmfetch: bevel nie gevind nie
hmmfetch: comandă negăsită
hmmfetch: comando não encontrado
hmmfetch: commande introuvable
hmmfetch: command not found
hmmfetch: käsku ei ole
hmmfetch: không tìm thấy lệnh
hmmfetch: komanda nerasta
hmmfetch: Kommando nicht gefunden.
hmmfetch: kommandot finns inte
hmmfetch: komut yok
hmmfetch: nie znaleziono polecenia
hmmfetch: níor aimsíodh an t-ordú
hmmfetch: no se encontró la orden
hmmfetch: no s'ha trobat l'ordre
hmmfetch: opdracht niet gevonden
hmmfetch: parancs nem található
hmmfetch: perintah tidak ditemukan
hmmfetch: príkaz nenájdený
hmmfetch: příkaz nenalezen
hmmfetch: команда не найдена
hmmfetch: командата не е открита
hmmfetch: 命令找不到
hmmfetch: コマンドが見つかりません