Relocating pubring.kbx in gpg.conf

[Konstantin Boyandin]

Hello,

GnuPG: 2.2.7 (built from sources), OS: Ubuntu 16.04.4 (64-bit).

Problem: file pubring.kbx is by default created in GnuPG default config 
directory. If some other files I can efficiently relocate in gpg.conf, 
i.e. by using something like

primary-keyring ~/mounted/gnupg/pubring.gpg
secret-keyring ~/mounted/gnupg/secring.gpg
trustdb-name ~/mounted/gnupg/trustdb.gpg
keyring ~/mounted/gnupg/pubring.gpg

but I see no obvious directives to relocate pubring.kbx - my only 
option, so it seems, remains relocating the entire configuration 
directory.

Is there a less total way to relocate pubring.kbx ?

Thanks.

Sincerely,
Konstantin