tpm_loadkey: command not found

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 CentOS possible default full paths are:

/usr/bin/tpm_loadkey - from package: tpm-quote-tools

You may install the required package with command yum install {package}

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