STUDIES ON THE CHEMISTRY OF LICHENS VII
449
L in k o et al. 6 and H a le , jr. ' described, in ad
dition to the free amino acids already mentioned
above, the detection of GluNH2, AspNH2, Sarc,
a-NH2-But, }'-NH2-But and Ethanolamine in extracts
from the lichen species Cladonia sylvatica and Pelti-
gera canina. It appears from their investigations
that Glutamic acid is predominating, in agreement
with the results from Lecanora Myrinii.
acid, compound F, eluted with Aspartic acid if the
temperature was changed to 50 . By the 33.5° run
the eluting compounds C and Urea will give a single
symmetrical peak. Nevertheless the compound C is
very likely not identical with Urea. The same rela
tion exists between the compound A and Phospho-
serine. One has not found any unambiguous proof
that the compound B is identical with the amino
acid Taurine, in spite of the fact that B completely
takes the place of Taurine in the elution pattern. It
is further clarified that the compound A is not iden
tical with Cysteic acid. By adding Cysteic acid to
the sample an unsymmetrical peak occurs. The com
pound E is not identical with Methionine sulphone.
On the basis of the work published by CONKER-
TON et al. 8 in 1968, the ratio of the areas under
the 440 nm and 570 nm absorption peak tracing
for Phosphoserine, Urea, Asp, Thr, Ser and the
compounds A, C, D and F, has been calculated. The
average of 0.13 for the ratio of the areas of the five
standard amino acids and the values of the unknown
peaks are compiled in Table 2. The results confirm
that the compounds A and C are not identical with
Phosphoserine or Urea.
The free amino acids found in the non-protein-
nitrogen fraction by the AAA *, agree well with those
detected by TLC. A remarkable feature of the thin
layer chromatographic analysis was the probable
content of GluNH2 and AspNHo. In the column
chromatographic amino acid determination with the
acid of AAA, the two acid amides give a single sym
metrical peak.
As it appears from Table 1 27 ninhydrin-positive
acids and related compounds have been determined
in the water extract from Lecanora Myrinii. One
noticed that Cystathionine, /5-Ala, /?-NH2-isobut
and Orn have been determined in small amounts.
Asparagine, glutamine, sarcosine,
cystine, cystathionine, tyrosine,
phenylalanine, ornithine, histidine,
ethanolamine, a-NH2-n-butyric acid,
<10
Standard amino acids
Unknown ninhydrin-
positive compounds
/S-NH2-isobutyric acid, ^-alanine,
Threonine, glycine, valine, methionine,
isoleucine, leucine, lysine,
>
10, <50
o-Phosphoserine
Urea
Aspartic acid
Threonine
Serine
0.13
Compound
Compound
Compound
Compound
A
C
D
F
0.25
0.21
0.17
0.12
0.11
0.14
0.13
0.12
Aspartic acid
y-NH2-n-butyric acid
Serine
Alanine
Arginine
90
150
180
180
280
310
1050
Proline
Glutamic acid
Table 2. The ratio of the areas under the 440 nm and 570 nm
absorption peak tracings for standard amino acids and for the
unknown compounds A, C, D and F of Lecanora Myrinii.
Table 1. Free amino acids of Lecanora Myrinii. The values
are calculated as mg amino acid per 1000 g ashless tissue.
All the unknown compounds in Lecanora Myrinii,
with the exception of compound B, hydrolyse or de
compose by boiling with hydrochloric acid. It is
therefore more than likely that more of these nin
hydrin-positive compounds may be peptides.
On the chart from AAA, six ninhydrin-positive
peaks which are different from any common amino
acid, were observed and termed, as seen in Fig. 1.
The figure shows the first part of the elution pat
tern obtained by applying an aliquot of the desalted
water extract to the long coloumn of the AAA. Other
unknown peaks did not appear in the rest of the
elution pattern and is therefore not reproduced here.
All the six unknown peaks are 570 nm peaks before
Aspartic acid. The unknown eluting before Aspartic
The unidentified compounds could not be charac
terised completely or identified because of insuffi
cient material. It would appear important to com
plete the identification of the unknown constituents
and to determine their chemical and biological signi-
cance. Work is in progress on the preparation of
larger amounts of material for that purpose.
6
7
P. l in k o , m .
a
l F t h a n , J. K.
m
ie t t in e n , and A. I. v ir -
8 E. J. c o n k e r t o n , E. E. c o l l , and R. L. o r Y , Analyt. Let
ters 1, 303 [1968].
* AAA = Amino Acid Analysen.
t a n e n , Acta chem. scand. 7, 1310 [1953].
E. a l e , J r ., The Biology of Lichens, London 1967.
h
Unauthenticated
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