A recombinant form of the sea raven type II antifreeze protein (SRAFP) has been produced using the Pichia pastoris expression system. The antifreeze activity of recombinant SRAFP is indistinguishable from that of the wild-type protein. The global fold of SRAFP has been determined by two-dimensional 1H homonuclear and three-dimensional 1H-¿15N¿ heteronuclear NMR spectroscopy using 785 NOE distan...

The existence of isospin admixtures in the physical Λ, π o complicates the extraction of ∆I = 3 2 non-leptonic hyperon decay amplitudes from experimental data, allowing contributions associated with large ∆I = 1 2 amplitudes to appear in the (nominally) ∆I = 3 2 amplitudes obtained ignoring these admixtures. We show how to correct for this effect to leading order in (m d − m u) and extract the ...

The beetle Cucujus clavipes is found in North America over a broad latitudinal range from North Carolina (latitude approximately 35 degrees N) to near tree line in the Brooks Range in Alaska (latitude, approximately 67 degrees 30' N). The cold adaptations of populations from northern Indiana (approximately 41 degrees 45' N) and Alaska were compared and, as expected, the supercooling points (the...

Using synthetic analogs of an alpha-helical winter flounder antifreeze polypeptide (AFP) we investigated some important molecular details of the mechanism of action of this AFP. Of the seven peptides synthesized, all but one were amino-terminal deletions of the native AFP. Three of the seven synthetic analogs possessed the same antifreeze activity as the native polypeptide; the other analogs we...

ABSTRACT We examined the ability of snow molds to grow at temperatures from -5 to 30 degrees C and to influence the growth of ice through assays for ice nucleation and antifreeze activities. Isolates of Coprinus psychromorbidus (low temperature basidiomycete variant), Microdochium nivale, Typhula phacorrhiza, T. ishikariensis, T. incarnata, and T. canadensis all grew at -5 degrees C, whereas Sc...

Ice-binding proteins (IBPs) assist in subzero tolerance of multiple cold-tolerant organisms: animals, plants, fungi, bacteria etc. IBPs include: (1) antifreeze proteins (AFPs) with high thermal hysteresis antifreeze activity; (2) low thermal hysteresis IBPs; and (3) ice-nucleating proteins (INPs). Several structurally different IBPs have evolved, even within related taxa. Proteins that produce ...

The structural heterogeneity of the major antifreeze peptides (AFPs) from the antarctic eel pout, Lycodichthys dearborni (formerly classified as Rhigophila dearborni) was characterized. Three major AFPs designated as RD1, RD2 and RD3, and five minor ones were isolated from the fish plasma. RD1 and RD2 are both 64 residues in length, about 7 kDa, and thus similar in size to all characterized typ...