In 2005, it was suggested that arsenic (which is known to be porphyrogenic) given to George III with antimony may have caused his porphyria. This study found high levels of arsenic in King Georges hair. In 2010, one analysis of historical records argued that the porphyria claim was based on spurious and selective interpretation of contemporary medical and historical sources. The mental illness of George III is the basis of the plot in The Madness of King George, a 1994 British film based upon the 1991 Alan Bennett play, The Madness of George III. The closing credits of the film include the comment that the Kings symptoms suggest that he had porphyria and notes that the disease is "periodic, unpredictable, and hereditary". The traditional argument that George III did NOT have porphyria, but rather bipolar disorder, is thoroughly defended by Andrew Roberts in his new biography, "The Last King of America." Descendants of George III. Among other descendants of George III theorized by the authors of Purple Secret to have had porphyria (based on analysis of their extensive and detailed medical correspondence) were his great-great-granddaughter Princess Charlotte of Prussia (Emperor William IIs eldest sister) and her daughter Princess Feodora of Saxe-Meiningen. They uncovered better evidence that George IIIs great-great-great-grandson Prince William of Gloucester was reliably diagnosed with variegate porphyria. Mary, Queen of Scots. It is believed that Mary, Queen of Scots, King George IIIs ancestor, also had acute intermittent porphyria, although this is subject to much debate.
The biosynthesis of the bleomycin aglycon can be visualized in three stages:

NRPS-mediated formation of P-3A from Ser, Asn, His, and Ala
PKS-mediated elongation of P-3A by malonyl CoA and AdoMet to yield P-4
NRPS-mediated elongation of P-4 by Thr to P-5 that is further elongated by β-Ala, Cys, and Cys to get P-6m.On the basis of the bleomycin structure and the deduced functions of individual NRPS and PKS domains and modules, a linear model for the bleomycin megasynthetase-templated assembly of the bleomycin peptide/polyketide/peptide aglycon was proposed from nine amino acids and one acetate. Biosynthesis of bleomycin is completed by glycosylation of the aglycones. Bleomycin naturally occurring-analogues have two to three sugar molecules, and DNA cleavage activities of these analogues have been assessed, primarily by the plasmid relaxation and break light assays. History
Bleomycin was first discovered in 1962 when the Japanese scientist Hamao Umezawa found anticancer activity while screening culture filtrates of Streptomyces verticillus. Umezawa published his discovery in 1966. The drug was launched in Japan by Nippon Kayaku in 1969. In the US, bleomycin gained FDA approval in July 1973. It was initially marketed in the US by the Bristol-Myers Squibb precursor, Bristol Laboratories, under the brand name Blenoxane. Research
Bleomycin is used in research to induce pulmonary fibrosis in mice. See also
Flagellate pigmentation from bleomycin
Pingyangmycin (Bleomycin A5)

References
Further reading
External links
"Bleomycin". Drug Information Portal. U.S. National Library of Medicine. "Bleomycin". European Medicines Agency (EMA).