Inhibition of L-Forms of Staphylococci by Coccal Forms of Staphylococci

Abstract

It was observed that coccal colonies of one strain of staphylococcus growing in the presence of a confluent growth of the L-forms of another strain of staphylococcus were surrounded by circular areas devoid of L-form growth. The purpose of this study was to determine to what extent coccal forms of one strain of staphylococcus inhibit L-forms or coccal forms of other strains of staphylococcus. The data indicate that coccal strains of Staphylococcus aureus znd of Staphylococcus albus show varying degrees of inhibition of growth of staphylococcal L-forms. This phenomenon appears to be related either to some toxic substance or to loss from the media of some unidentified nutritional factor. Alpha-hemolysin was shown not to be responsible for this effect.Materials and Methods. The term L-form has been defined in detail in previous reports from this department (1-3).Nine strains of staphylococcus (six S. aureus and three S. albus) and their derived L-forms were studied. The L-forms were induced with methicillin except No. 3 16, which was isolated directly from sputum of a patient with cystic fibrosis of the pancreas. Eight of the strains were from patients and one from the American Type Culture Collection (6538P).The coccal forms were maintained on brain healrt infusion (BHI) agar slants (Difco) .The L-colonies were induced and maintained cin the same medium, to which 10% inactivated horse serum, 0.1 % MgS04-7H20, 3.5% NaCl, and 250 ,ug/ml of sodium methi-Isupported in part by USPHS Grant No. SROl-Al07790 from National Institute for Allergy and Infectious Diseases. cillin were added (SSM, salt serum methicillin). Streaks of L-form colonies were transferred from the SSM plates to an L-form maintenance medium without methicillin (SS) ( 1 ) . Streaks of parent colony growth were made a t right angles across streaks of L-forms. On other plates L-forms of one strain were streaked across streaks of L-forms of other strains. The plates were inverted and maintained under aerobic conditions at 3 7".

CharmlessB→Khη(′)decays withKh=KCheng1, Chua2 2010Phys. Rev. D545922View full textAdd to dashboardCite

“…(27) below. The flavor operators p i and the annihilation operators p i are related to the coefficients a p i and b p i by (5) and…”

“…Applying the anomalous equation of motion Eq. (A7) and neglecting the masses of u and d quarks, one gets [27,28] h ð 0 Þ j" s 5 sj0i ¼ Ài…”

Final state interactions for B→VV charmless decays

“…VV have produced considerable theoretical interest, see, e.g., the recent papers [7][8][9][10]. Data for the branching ratios (BR) and the polarization fractions for a few decay channels are reported in Table I.…”

“…Since momenta of the final particles are hard, the application of the method involves large extrapolations and the method is questionable (see e.g. [10]). A possible answer consists of introducing some correction.…”

Semi-inclusive hadronicBdecays in the endpoint region

“…XM have received much less attention over the years in contrast to the widely studied exclusive two-body B decays [1][2][3][4][5][6][7][8][9]. As we will show in this paper, semi-inclusive hadronic B decays in the endpoint region, where M is an isolated energetic meson and X is a collinear jet of hadrons in the opposite direction, are theoretically simpler than the exclusive two-body B decays in many respects, yet still address many of the questions that had been debated in the context of the two-body B decays.…”