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The article presents research on the infection by the microsporidian Glugea hertwigi of rainbow smelt, Osmerus mordax, in Prince Edward Island, Canada. Based on observations, there was a 24% prevalence of infection out of 187 examined fish captured in February and March 2009. Only mature pores were examined from the large and small xenomas of Glugea hertwigi observed within the submucosa of the gastrointestinal tract and along the mesentery of the host. Results showed that the affinity of the parasite to ovarian tissue may vary depending on host, parasite, or environmental factors.

Two minor radioactive products in cultures of G. fujikuroi strain ACC917 supplemented with labeled gibberellin A4 have been identified as the 2alpha-hydroxy derivative, gibberellin A47, and the hydrate, gibberellin A2. In addition, evidence was obtained by combined gas chromatography--mass spectrometry for the formation of 3-O-acetylgibberellin A1,3-O-acetylgibberellin A3, and gibberellin A20 by the culture. The time course of gibberellin synthesis in defined and complex media, as well as changes in the relative amounts of radioactive gibberellins formed when [4C]gibberellin A4 was added to cultures at different ages, suggest that the composition of the gibberellin mixture produced is determined by the balance between synthesis and decay of key enzymes in the branching pathway.