SUMMARYLysostaphin attacked both viable staphylococci and the mucopeptide portion of the staphylococcal cell wall. In the absence of salts, lysostaphin activity could only be recovered from the particulate portion of the lysed cell after centrifugation, whereas in the absence of salts its action on the mucopeptide resulted in a recovery of active material in both the sediment and the supernatant fluid. It appears from these observations that lysostaphin is complexed with its substrate and that NaCl is required to break the complex.
Portions of a whole antiserum to Histoplasmna capsdlaituln were recacted with amounts of fluorescein isothiocyanate (FITC) that ranged from 50 to 400 ,ug/mg of protein. Portions of the globulin from the same antiserum were reacted with amounts of FITC that ranged from 12.5 to 50 ,ug of FITC per mg of protein. The globulin conjugates (postlabeled globulins), the whole serum conjugates, and the globulins from the whole serum conjugates (prelabeled globulins) were compared with respect to their fluorescein-protein (F: P) ratios and fluorescent-antibody (FA) activities. The whole serum sample treated with 50,ug of FITC per mg of protein was least reactive in FA tests, and its globulin had the lowest F: P. All other conjugates had globulins with F:P ratios that were considered to be adequate for high FA activity. It was found, however, that the prelabeled globulins were considerably less reactive than the postlabeled globulins or the whole serum conjugates. A larger amount of brightly staining reagent per milliliter of original serum could be obtained from labeled whole serum than from postlabeled globulin. Lissamine-rhodamine conjugated to bovine serum albumin (LRBSA) was evaluated as a counterstain to be used in conjunction with FITC-labeled whole antisera. The counterstain was effective in masking nonspecific FITC fluorescence in Formalin-fixed tissues and in culture smears of fungi. Masking was incomplete in culture smears of a bacterium and in blood smears containing a protozoan.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.