-transparent.png){kind=logo}
When urine samples from alkaptonuria patients are allowed to stand, they turn black, presumably owing to the oxidation of homogentisic acid to a melanin-like substance. We report the characterization of the pigments formed by polymerization of (a) the components in the urine from a patient with alkaptonuria and (b) homogentisic acid. The absorption spectra and electron spin resonance signals of these pigments are similar to those of eumelanins. Irradiation of the pigments with nitroblue tetrazolium caused reduction of the tetrazolium; this was partially inhibited by superoxide dismutase. Irradiation of Ehrlich ascites carcinoma cells with the pigments from homogentisic acid or urine caused cell lysis. Since this lysis was inhibited by catalase, we have concluded that it was mediated by H2O2. A similar pigment was also extracted from the tissue from an alkaptonuria patient. It is suggested that the degeneration of tissue in vivo may be due to the deposition of melanin-like pigments in the tissues, probably in combination with metal ions.
I A Menon, and
S D Persad, and
H F Haberman, and
P K Basu, and
J F Norfray, and
C C Felix, and
B Kalyanaraman
January 2017,
JIMD reports,
I A Menon, and
S D Persad, and
H F Haberman, and
P K Basu, and
J F Norfray, and
C C Felix, and
B Kalyanaraman
August 1986,
Clinical chemistry,
I A Menon, and
S D Persad, and
H F Haberman, and
P K Basu, and
J F Norfray, and
C C Felix, and
B Kalyanaraman
January 2017,
JIMD reports,
I A Menon, and
S D Persad, and
H F Haberman, and
P K Basu, and
J F Norfray, and
C C Felix, and
B Kalyanaraman
December 1905,
The Journal of physiology,
I A Menon, and
S D Persad, and
H F Haberman, and
P K Basu, and
J F Norfray, and
C C Felix, and
B Kalyanaraman
January 1988,
Voprosy meditsinskoi khimii,
I A Menon, and
S D Persad, and
H F Haberman, and
P K Basu, and
J F Norfray, and
C C Felix, and
B Kalyanaraman
February 1969,
Biochimica et biophysica acta,
I A Menon, and
S D Persad, and
H F Haberman, and
P K Basu, and
J F Norfray, and
C C Felix, and
B Kalyanaraman
January 1971,
Journal de pharmacie de Belgique,
I A Menon, and
S D Persad, and
H F Haberman, and
P K Basu, and
J F Norfray, and
C C Felix, and
B Kalyanaraman
December 2009,
Human mutation,
I A Menon, and
S D Persad, and
H F Haberman, and
P K Basu, and
J F Norfray, and
C C Felix, and
B Kalyanaraman
October 1973,
Zeitschrift fur klinische Chemie und klinische Biochemie,
I A Menon, and
S D Persad, and
H F Haberman, and
P K Basu, and
J F Norfray, and
C C Felix, and
B Kalyanaraman
July 1964,
Orvosi hetilap,
