bp_seqretsplit: 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/bp_seqretsplit - from package: bioperl

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