Backtics are considered 'old school'. Here is an option using perl %ENV: 
export INP2="A String of Text"
RES=$(perl  -e '($x=$ENV{INP2})=~s/String/Wall/;print $x')
echo $RES
A Wall of Text

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        The best defense against logic is ignorance.

In reply to Re: Embedding perl in bash by NetWallah
in thread Embedding perl in bash by wackattack

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