抄録
The phosphorus metabolism of growing surface colonies of Aspergillus niger was investigated, 32P-Phosphate was found to be incorporated most actively at the growing margin, thereafter to be translocated, not recognizably laterally, but upwardly toward conidia through the conidia-forming apparatus. It was observed that with the progress of conidia formation the macromolecular phosphorus compounds (RNA, DNA and polyphosphate) in hyphae underwent active turnover. Evidence was presented showing that there are at least two sites of biosyntheses of P-containing macromolecules in a growing colony, one being located at the lower layer (substrate mycelia) and the other at the upper layer (aerial mycelia) of the mat. The bulk RNA's synthesized at different sites in the mat was shown to be different in their chemical nature. Based on these and other observations, it was inferred that the P- containing macromolecules synthesized in the upper layer would be translocated into conidia without being accompanied by their decomposition or transformation. Discussions were made on such views with reference to the cytochemical and electronmicroscopical observations made earlier of the mold colonies by the present authors and other workers.
