KW: protoplasts; penicillin; L-forms; spheroplasts; Dienes; Klieneberger-Nobel; DAP, diaminopimelic acid; My interest in L-forms had several sources. They had played a part in pre-1946 imaginations of cellular changes in bacteria; even "zygospores" - Mellon - .. to the point that Louis Dienes had been invited to one of the Cold Spring Harbor Symposia; and I had visited Dienes in Boston. Cf also Amsterdamskaya papers re cyclogeny. Zinder & I had seen strange, filtrable forms in early interpretations of transduction; I even expanded on that in CSH 1951. That blew up of course and "FA" became phage. Nevertheless, after reading Weibull and Zinder on formation of protoplasts with lysozyme, and their stabilization with hypertonic sucrose; it came to me that penicillin-lysis might be intermediated by osmotically fragile wall-defective forms; and one Saturday afternoon experiment substantiated that. While this was the first rationally based examination of these odd forms, there remain many mysteries -- the role of agar, permanent L-forms; mg++; and what can be done with them icw cell fusion. L-forms also play some odd role in persistent, antibiotic-resistant chronic infection esp. streptococci. More: LOOKUP: exact interplay of Zinder, Weibull articles.; Correction: bibliographic reference to WORK, E. 1957 Biochemistry of the bacterial cell wall. Nature, 179, l-16. -- should be pp.841-847 The 1-16 doubtless refers to pagination of a reprint I had; DAP analogues have been explored as antimicrobials: RJ Cox and others.; jl 12/15/98; 1/24/99; 8/20/02
