I was doing cell lysis via sonication on transformed BL2:DE3 pLysS E.coli cells, expressing recombinant target proteins. After sonication and centrifugation, the supernatant was transferred to a fresh tube without keeping the working sample on ice for about 5-7 mins. Do you reckon this will affect my recombinant protein purity due to induced protease activity because of this? Various protease inhibitors and lysozyme were added to the samples prior to sonication. Thank you in advance!