His research focuses on metal-dependent regulation of protein function, with particular emphasis on zinc biology—including metalloproteins obtain their metal ions under cellular conditions and how these ions control protein structure, stability, and activity. His group also develops fluorescent and regioselective chemical tools for multifunctional protein labeling, as well as analytical methods for monitoring intracellular metal-ion fluctuations. Prof. Krężel’s work integrates protein engineering, synthetic chemistry, structural mass spectrometry, biophysical and computational approaches, and molecular/structural biology.

Prof. Krężel has co-authored ~150 peer‑reviewed publications and has presented at numerous international scientific conferences, including invited, keynote, and plenary lectures.  He has served as Principal Investigator on 14 research grants and acts as a reviewer for major funding agencies and journals. He is an Editor of Biometals (Springer Nature). His contributions have been recognized with major distinctions, including the POLITYKA Passport for research achievements and the Bogusława and Włodzimierz Trzebiatowski Medal of the Polish Chemical Society for accomplishments in inorganic chemistry.