654
R. H. THOMSON
Plastoquinone also appears in the Gymnospermae. It was detected
spectroscopically in pine needles in the original work of Kofler (78)
and was isolated recently from the leaves of the maidenhair tree
(Ginkgoaceae) (80).
2. Fungi
a. Benzoquinones. Almost all the fungal benzoquinones are produced
by Hyphomycetes or Basidiomycetes, the majority having a very limited
distribution. Oosporein (LXXXVI) and the coenzymes Q (p. 692)
occur more widely. In no case has the same quinone been obtained
from both higher and lower fungi, although quinones of similar structure
occur in both classes. All the terphenylquinones are found in Basidiomycetes with the exception of the hyphomycetous pigment volucrisporin
(LXXXIX), and all the simpler quinones are formed by Hyphomycetes
save (LXXXVII), which is produced by two Basidiomycetes when
grown on corn-steep-glucose media. Thus, with the exceptions noted,
the fungal benzoquinones can be divided into (a), simple derivatives
of benzoquinone and toluquinone, (LXXVI) to (LXXXIV), and the
related diquinones (LXXXV) and (LXXXVI), which are produced by
Hyphomycetes on synthetic media, and (b), the terphenylquinones,
(LXXXVII) to (XCII), obtained from Basidiomycetes growing wild.
The simplest fungal quinone is gentisylquinone (LXXVI), which
appears as a deep-violet quinhydrone, (C 7 H 8 0 3 ) 3 , C 7 H 6 0 3 , in cultures
of Penicillium patulum Bainier (97). It is the only benzoquinone bearing a hydroxymethyl group, a common structural feature in the anthraquinone series. In recent work with a nonpigmented mutant strain of
P. patulum, Tanenbaum and Bassett (98) have isolated several simple
aromatic compounds including gentisyl alcohol [the quinol of
(LXXVI)], gentisaldehyde, and gentisic acid. Auroglaucin and flavoglaucin (LXXXII) are substituted gentisaldehydes (orange and yellow, respectively) formed by numerous species of the Aspergillus
glaucus series (along with anthraquinone pigments) (99). Another
highly colored quinol is 2,4,5-trihydroxyphenylglyoxylic acid, a bright
red metabolic product of Polyporus tumulosus Cooke (100).
Spinulosin (LXXXIV), the first fungal quinone to be identified, was
originally obtained from cultures of Penicillium spinulosum Thorn by
Birkinshaw and Raistrick (101) and was the forerunner of numerous
quinones which were isolated later in their laboratory. It is also formed
by Aspergillus fumigatus Fresenius (102), another strain of which produced the closely related quinone fumigatin (LXXXIII) (103). Like
several of the simple quinones shown on page 656, spinulosin shows
fairly high antibiotic activity. The diquinones oosporein (LXXXVI)
R. H. THOMSON
Plastoquinone also appears in the Gymnospermae. It was detected
spectroscopically in pine needles in the original work of Kofler (78)
and was isolated recently from the leaves of the maidenhair tree
(Ginkgoaceae) (80).
2. Fungi
a. Benzoquinones. Almost all the fungal benzoquinones are produced
by Hyphomycetes or Basidiomycetes, the majority having a very limited
distribution. Oosporein (LXXXVI) and the coenzymes Q (p. 692)
occur more widely. In no case has the same quinone been obtained
from both higher and lower fungi, although quinones of similar structure
occur in both classes. All the terphenylquinones are found in Basidiomycetes with the exception of the hyphomycetous pigment volucrisporin
(LXXXIX), and all the simpler quinones are formed by Hyphomycetes
save (LXXXVII), which is produced by two Basidiomycetes when
grown on corn-steep-glucose media. Thus, with the exceptions noted,
the fungal benzoquinones can be divided into (a), simple derivatives
of benzoquinone and toluquinone, (LXXVI) to (LXXXIV), and the
related diquinones (LXXXV) and (LXXXVI), which are produced by
Hyphomycetes on synthetic media, and (b), the terphenylquinones,
(LXXXVII) to (XCII), obtained from Basidiomycetes growing wild.
The simplest fungal quinone is gentisylquinone (LXXVI), which
appears as a deep-violet quinhydrone, (C 7 H 8 0 3 ) 3 , C 7 H 6 0 3 , in cultures
of Penicillium patulum Bainier (97). It is the only benzoquinone bearing a hydroxymethyl group, a common structural feature in the anthraquinone series. In recent work with a nonpigmented mutant strain of
P. patulum, Tanenbaum and Bassett (98) have isolated several simple
aromatic compounds including gentisyl alcohol [the quinol of
(LXXVI)], gentisaldehyde, and gentisic acid. Auroglaucin and flavoglaucin (LXXXII) are substituted gentisaldehydes (orange and yellow, respectively) formed by numerous species of the Aspergillus
glaucus series (along with anthraquinone pigments) (99). Another
highly colored quinol is 2,4,5-trihydroxyphenylglyoxylic acid, a bright
red metabolic product of Polyporus tumulosus Cooke (100).
Spinulosin (LXXXIV), the first fungal quinone to be identified, was
originally obtained from cultures of Penicillium spinulosum Thorn by
Birkinshaw and Raistrick (101) and was the forerunner of numerous
quinones which were isolated later in their laboratory. It is also formed
by Aspergillus fumigatus Fresenius (102), another strain of which produced the closely related quinone fumigatin (LXXXIII) (103). Like
several of the simple quinones shown on page 656, spinulosin shows
fairly high antibiotic activity. The diquinones oosporein (LXXXVI)