Root hair cell enhancement in tissue cultures from soybean roots: a useful model system: in vitro Rhizobium symbiosis

A technique for obtaining large numbers of root hair cells in cell cultures from soybeans is described. The cells were grown on agar containing the Prairie Regional Laboratory B5 (PRL-B5) medium for periods longer than 60 days. Mixed populations of cultured root hair cells and cortical cells were used to study the in vitro association between soybean cells and Rhizobium japonicum. The advantages of these types of root cell cultures in studies of symbiosis are discussed.     

Sterols of Glaucocystophytes

Glaucocystophytes are a group of evolutionarily important freshwater algae that have an almost intact cyanobacterium, referred to as a cyanelle, as the photosynthetic organelle. Because of this, they have been the subject of a large number of studies over the past few decades on how a cyanobacterium transitioned into a chloroplast. However, studies on their lipid composition have lagged behind those on other areas of glaucocystophyte cell biology. To this end, we have examined the sterol composition of Cyanophora paradoxa Korshikov and Glaucocystis nostochinearum Itzigsohn in order to identify sterols left unidentified in previous studies. We have found that two isolates of G. nostochinearum and one of C. paradoxa uniformly produced three sterols: 24‐methylcholest‐5‐en‐3β‐ol, 24‐ethylcholesta‐5,22E‐dien‐3β‐ol, and 24‐ethylcholest‐5‐en‐3β‐ol.