In an effort to increase the thermostability of Moloney Murine Leukemia Virus reverse transcriptase (MMLV RT), we screened random and site-saturation libraries for variants that show increased resistance to thermal inactivation. We discovered five mutations E69K, E302R, W313F, L435G and N454K that collectively increase the half-life of MMLV RT at 55 degrees C from less than 5 min to approximate...

The thermal stability of horseradish peroxidase suspensions was studied in three organic solvents of different hydrophobicity (dodecane, octane, and 1-octanol) at three different water contents (14.1, 55.3 and 256.2 mg water g dry protein). In these conditions, the enzyme is much more stable than in aqueous solutions (inactivation temperatures were in the range of 125–1508C). The enzyme showed ...

1. Apo-superoxide dismutase was more labile toward a variety of inactivating stresses than was the holoenzyme. 2. cu++ restored catalytic activity to the apoenzyme and markedly enhanced its thermal stability but Cu++ plus Zn++ were needed to attain the stability of the native enzyme. 3. Co’-+ or Hgii were able to replace Zn++ in increasing the thermal stability of the Cu+f-repleted apoenzyme. I...

Thermal perturbation techniques have been used to probe structural features of the nicotinic acetylcholine receptor (AcChR). The information obtained from differential scanning calorimetry (DSC) of AcChR membranes (M.C. Farach and M. Martinez-Carrion (1983) J. Biol. Chem. 258, 4176) in the absence and in the presence of cholinergic ligands and local anesthetics, is comparable to that obtained f...

Heating the Sabin strains of poliovirus at 42 to 45 degrees C caused inactivation, loss of native antigen, and release of the viral RNA (vRNA). The loss of virion infectivity exceeded the loss of vRNA infectivity (as measured by transfection) by roughly 2 log10. Pirodavir inhibited the loss of native antigen and RNA release and reduced the loss of virion infectivity to the same level as the los...

The effect of high pressure thermal (HPT) processing on the inactivation of spores of proteolytic type B Clostridium botulinum TMW 2.357 in four differently composed low-acid foods (green peas with ham, steamed sole, vegetable soup, braised veal) was studied in an industrially feasible pressure range and temperatures between 100 and 120°C. Inactivation curves exhibited rapid inactivation during...

A resurgence in interest examining thermal pasteurization technologies has been driven by demands for "cleaner" labeling and the need of organic and natural foods markets for suitable preventive measures to impede microbial growth and extend shelf life of minimally processed foods and ready-to-eat foods with a concomitant reduction in the use of chemical preservatives. This review describes the...