Dr. A. N. Richards

2101 Constitution Avenue

Washington 25, D.C.

Dear Dr. Richards:

The work on penicillin, which we have not prosecuted very intensively because of other activities, has so far not provided any very promising results. I inclose [sic] a report by Professor Dan H. Campbell on the work which has been carried out.

Cordially yours,

Linus Pauling

LP:fh

1 inc.

[2]

REPORT FOR RICHARDS

The first study of penicillin was an attempt to combine it with glyoxal0treated serum albumin. No combination was obtained. The glyoxal had no effect on the activity of the penicillin. Since serum proteins tend to associate of polymerize under the influence of denaturing agents, experiments were carried out to determine whether penicillin would be incorporated into such protein complexes. The denaturing agents and conditions studied were urea, moderately high temperatures, and alkaline pHs. It was found that these denaturing agents and conditions have little effect on penicillin activity in the absence of protein, but that the apparent activity is rapidly lost when human serum albumin is added. Studies are still in progress to determine if this is an actual destruction of penicillin, or is due to association of the penicillin molecules with the relatively large non-diffusible albumin molecules. This is being determined by studies on the amount of penicillin excreted from injected rabbits. Results obtained so far are not conclusive, but indicate that serum albumin actually inactivates the penicillin.

Dan H. Campbell