Abstract
Abstract Lysostaphin is a zinc-metalloenzyme which has a molecular weight of 25,000 when determined by sedimentation equilibrium in dilute aqueous salt solutions. Combination of the sedimentation coefficient, s20,w = 2.32, and diffusion coefficient, D20,w = 7.83, gave a native molecular weight of 25,800. Sedimentation equilibrium of the protein in 6 m guanidine hydrochloride, with and without 2-mercaptoethanol, gave molecular weights of 25,800 and 27,800, respectively. The molecular weight of the fully dissociated protein was also determined to be 24,500 by the technique of gel filtration in 6 m guanidine hydrochloride and 25,500 by polyacrylamide gel electrophoresis in sodium dodecyl sulfate. In each case, only a single protein species was shown to be present. These data indicate that the lysostaphin molecule is a single polypeptide chain. The frictional coefficient ratio for lysostaphin of 1.39 is higher than values obtained for most globular proteins. The optical rotatory dispersion spectrum was also different from that invariably observed with globular proteins and revealed no evidence of helical structure in the molecule. The amino acid composition of lysostaphin was unusual in that half-cystine was found to be absent.
Highlights
Lysostaphin is a zinc-metalloenzyme which has a molecular weight of 25,000 when determined by sedimentation equilibrium in dilute aqueous salt solutions
We report here some of the properties of lysostaphin, including molecular weight, amino acid composition, and gross conformational structure
Electrophoresis-Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate was carried out according to the method of Shapiro, Vifiuela, and Maize1 [3] as extended by
Summary
Electrophoresis-Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate was carried out according to the method of Shapiro, Vifiuela, and Maize1 [3] as extended by. Weber and Osborn [4]. Amino Acid Composition--Amino acid analyses were performed by the accelerated system of Hubbard [5] on a Spinco model. Duplicate samples were hydrolyzed by 6 N HCl under vacuum for 24, 48, and 72 hours at 110” [6]. Cystine and cysteine were determined as cysteic acid by the performic acid oxidation method of Moore [8]. Sedimentation and Diffusion Coeficients-All experiments were performed with a Spinco model E analytical ultracentrifuge. Sedimentation and diffusion coefficients were determined at 25”
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
