FACTORS AFFECTING PROTOPLAST FORMATION AND REGENERATION OF STREPTOMYCETES
XU XIAO-XUE,ZHANG TING-LAN AND ZHENG YOU-XIA (Shanghai Institute of Plant Physiology,Academia Sinica)
This paper reports the effects ofthe component of growth medium,growth phase of mycelium,lytic temperature,and components of regeneration medium on protoplast formation and regeneration of S.qingfengmy-ceticus and S.hygroscopicus var.jinggangen-sis. The results shows that 1) My-celia grown on the media supplemen-ted with appropriate amount of gly-cine and/or sucrose increase the susceptibility to lysozyme.2) Regeneration rate of protoplasts from exponential phase mycelium is much higherthan that of stationary phase my-celium 3) Optimal lytic temperature is 28℃ for S.qingfengmyceticusand 32℃ for S.hygroscopicus var.jing-gangensis.4) Protoplast regenerationis markedly affected by the concentration of hypertonic stablizer in theregeneration medium. The possible mechanisms of theaction of glycine and sucrose on lysozy-me susceptibility to streptomycetes cellwall and the possible reasons of theoccurrence of different ratio of osmotic unstable protoplasts in differentstreptomycetes protoplast preparationare discussed.