Sommer N F, Creasy M T, Maxie E C, Romani R J
Department of Pomology, University of California, Davis, California.
Appl Microbiol. 1963 Nov;11(6):463-6. doi: 10.1128/am.11.6.463-466.1963.
Irradiated sporangiospores of Rhizopus stolonifer excreted pectolytic enzymes, which hydrolyzed pectin and macerated potato tuber discs, into the suspending medium. Pectin glycosidase, but not pectin methylesterase, activity developed regardless of the amount of radiation the spores had received, unless the dose exceeded about 1 megarad. The ability to produce pectolytic enzymes was found to be more radiation-resistant than the potential for colony formation or the ability to germinate. Spores made incapable, through irradiation, of forming colonies continued to produce pectolytic enzymes after a 6-day period following irradiation treatment.
匍枝根霉的辐照孢子囊孢子将果胶分解酶分泌到悬浮培养基中，这些酶可水解果胶并使马铃薯块茎切片浸软。无论孢子接受的辐射量如何，果胶糖苷酶（而非果胶甲酯酶）的活性都会产生，除非剂量超过约1兆拉德。研究发现，产生果胶分解酶的能力比形成菌落的潜力或发芽能力更具抗辐射性。经辐照而无法形成菌落的孢子在辐照处理后的6天内仍继续产生果胶分解酶。
