The pigmented strain Serratia marcescens ATCC 274 had a higher buffering capacity and a higher membrane H conductance than S. marcescens GP, a spontaneous nonpigmented mutant of ATCC 274. The data suggest that mutations which apparently affect only the synthesis of a secondary metabolite can modify buffering capacity and passive H conductance.

Proof. [Solution due to Claudiu Raicu] Consider two polynomials f, g ∈ C[X±] such that the spherical graphs they determine intersect transversely at the points where the vectors vi intersect the sphere. This implies that T (f) and T (g) intersect transversely ([1]) at each point and T (f)∩T (g) = Σ. Using the Transverse Intersection Lemma (lemma 3.2, corollary 3.3 of [1]) we get that Σ = T (f, ...

Vaccinia topoisomerase forms a covalent protein-DNA intermediate at 5'-CCCTT downward arrow sites in duplex DNA. The T downward arrow nucleotide is linked via a 3'-phosphodiester bond to Tyr-274 of the enzyme. Here, we report that mutant enzymes containing glutamate, cysteine or histidine in lieu of Tyr-274 catalyze endonucleolytic cleavage of a 60 bp duplex DNA at the CCCTT downward arrow site...