A deliberately ‘dirty’ performance of this time-honoured theme. Just the five tones, no semitones.
Note that there is a practice-speed version of the theme for play-along learning at the end of the video.
You don’t need to play the theme as fast as here, or copy the end-of-phrase octave-roll drumming accurately.
The thing to 'get' is the melodic contour - the same/up/down formula.
The contour formula repeats:
[start] same - down - up - down - same - down - up - down - same (etc.) but ends down - up - down - down - down - up.
The theme here is offered as a four-strain chorus in both A and B minors - for the 'transposing bonus'.
So it’s an AABA form, either way you look at it!
D and E minors would give you another all-white-key version of
this AABA arrangement.
You should aim to be able to ‘see-and-hear’ this riff practically anywhere on the keyboard in your mind's eye.
Pick your starting note, quickly revise your five pentatonic tone and apply the same/up/down melodic contour formula.
Then go to the keyboard and 'check your results'.
Try singing along! Anybody can sing the blues - you don't have to be the least bit in tune. Ten minutes of pentatonics will give your mojo a boost any time of day!