Determination of cyclic adenosine phosphate and protein content in dormant chlamydospore and nondormant chlamydospore of Arthrobotrys flagrans

Arthrobotrys flagrans, a nematode-eating fungus, is an effective component of animal parasitic nematode biocontrol agents. In the dried formulation, the majority of spores are in an endogenous dormant state. This study focuses on dormant chlamydospore and nondormant chlamydospore of A. flagrans to investigate the differences in cyclic adenosine monophosphate (cAMP) and protein content between the two types of spores. cAMP and soluble proteins were extracted from the nondormant chlamydospore and dormant chlamydospore of two isolates of A. flagrans. The cAMP Direct Immunoassay Kit and Bradford protein concentration assay kit (Coomassie brilliant blue method) were used to detect the cAMP and protein content in two types of spores. Results showed that the content of cAMP in dormant spores of both isolates was significantly higher than that in nondormant spores (p < 0.05). The protein content of dormant spores in DH055 bacteria was significantly higher than that of nondormant spores (p < 0.05). In addition, the protein content of dormant spores of the SDH035 strain was slightly higher than that of nondormant spores, but the difference was not significant (p > 0.05). The results obtained in this study provide evidence for the biochemical mechanism of chlamydospore dormancy or the germination of the nematophagous fungus A. flagrans.