669 Addendum 



It might be pointed out that, formally, some of the 

 vulpinic acids are tetronic acids although we have not 

 classified them as such. 



The chemistry of the tetronic acids has been reviewed.^® 



5. Carotenes and Carotenoids 



Another paper has been published on the incorporation 

 of C^Mabeled compounds into carotenes by Neiirospora 

 crassa.^'^ Mevalonic acid salts were the best of eight pre- 

 cursors used, but less than 1 percent of the 2-C'* activity 

 was incorporated into the carotene fraction. Phytoene, y- 

 carotene and its isomers (fS- and ^-), phytofluene, neuro- 

 sporene, spirOloxanthin and its isomers and lycopene 

 were isolated. The presence of much phytoene, whose 

 presence in the theoretical biosynthetic sequence has been 

 questioned, was taken as an argument against formation 

 of the carotenes by stepwise interconversions involving 

 either hydrogenation or dehydrogenation and as an indi- 

 cation, rather, of independent synthesis. 



The major carotenoids of some ascomycetes and basid- 

 iomycetes have been identified. *° /^-Carotene was predom- 

 inant in Epichloe typhina and Helotium citrinum. Crypto- 

 xanthin was second in importance in Calocera viscosa. 

 Neurosporene was the major carotenoid in dull yellow 

 Cantharellus infundibiliformis with traces of lycopene 

 present. The reverse was true in Cantharellus lutescens. 

 No carotenoids, but instead pigments with quinone-Hke 

 reactions, were detected in the grey Cantharellus cinereus 

 and orange-red Giiepinius helvelloides. 



A red pigmented yeast isolated from root nodules of 

 Lupinus luteus produced torulene, ^-carotene, y-carotene 

 and torularhodin.*^ Diphenylamine inhibited production 

 of y-carotene and torularhodin. 



Rhodotorula mucilaginosa contained, in decreasing or- 



38 L. J. Haynes and J. R. Plimmer, Quart. Revs. 14 292 (1960). 



33 Leo F. Krzeminski and F. W. Quackenbush, Arch. Biochem. and 

 Biophijs. 88 287 (1960). 



*o Gilbert Turian, Arch. Mikrobiol. 36 139 (1960). 



" Gy. Schneider, B. Matkovics and J. Zsolt, Acta. Univ. Szegedien- 

 sis. Acta. Phys. et Chem. 5 55 (1959). 



