We examined the outer membrane proteins which appear during the growth of Neisseria gonorrhoeae F62 in complex medium supplemented with 25 microM Desferal mesylate, a potent iron chelator. Outer membranes were prepared by Sarkosyl extraction and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Several higher-molecular-weight (74,000 to greater than 94,000) proteins increased under iron-limiting conditions. In addition we observed the appearance of an iron-regulated protein with an apparent molecular weight of 37,000. This protein comigrated with the gonococcal protein I under normal Laemmli gel conditions. By increasing the ionic strength of the lower gel buffer, separation of protein I and the 37,000-dalton iron-regulated protein occurred. The 37,000-dalton protein stained poorly with Coomassie blue. However, when a silver stain was used, the protein appeared as a major component of the gonococcal outer membrane. Production of this 37,000-dalton protein was suppressed by the addition of iron to the medium. An iron-regulated protein with a similar molecular weight was observed in four clinical isolates and in an additional laboratory strain. Peptide mapping indicated that the 37,000-dalton protein was distinct from protein I and was identical between strains of the WI and WII serogroups.

While there has been emphasis on the institution and individual classroom as loci of learning and reform, less attention has been paid to the academic department. However, precisely because its structure is so endemic to institutions of higher education, the academic department may be the most logical and potent site for change. Using a case study approach, this paper examines the conditions under which change in undergraduate education takes hold and flourishes in the academic department, advances the concept of readiness, and explores its implications for those who wish to promote change in the department.

~~~~ ~The nutritional requirements of 43 strains of Haemophilus injluenzae isolated from clinical and normal flora sources were investigated. Two defined minimal media were developed by modifying the medium of Herriott et al.( 1 970) : 74 % of the strains could grow on the minimal media and Herriott's medium; the remaining strains could not grow on any of these media.

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An acute inhalation exposure of laboratory mice to respirable Mn3O4 aerosols is described. The generation system consisted of a Wright dust generator which produced 1.40 micrometer aerosols. A non-linear loss of deposited manganese from mouse lungs over the inital 24-hour post-exposure period was observed. Systemic distribution of the manganese was observed in various tissues following exposure.