Members of the genus
Micromonospora
show a complex life cycle which normally involves the presence of substrate or vegetative mycelia and sporulation with single spores born on the vegetative hyphae followed by the synthesis of a dark extracellular polysaccharide. Bergey’s Manual states that micromonosporae rarely produces aerial mycelia (AM) and if so, is considered “
sterile
”. During the characterisation of novel micromonosporae from the Sea of Cortes, it was observed that AM is produced reproducibly in the presence of certain carbon and/or nitrogen sources. Micromanipulation of the AM subcultured onto fresh media produced colonies; hence, this structure should not be called “
sterile
”. TEM of the AM producing isolates suggests that the spores also show activity as reported for bacilli of marine origin. This would be the first report of the presence of “inducible” AM in micromonosporae of marine sources and that the spores of this genus have a role other than just dispersal.
ETQ and LAMM thank Abigail Martínez Torres, Mariela Segura del Pilar and Edgar Oliver López Villegas (EOLV) for technical assistance, mostly for the SEM and TEM studies. Figure 1 was taken by Wendy M. Lara González. Part of this work was supported by grants DGAPA-UNAM (PAPIIT IN212011) to LAMM and CONACyT I010/665/12 C-460/2012 to ETQ. This work was part of a collaborative agreement between UNAM and IPN (collaborative agreement UNAM 32939-2163-16-X-12).
Conflict of Interest
The authors declare no conflict of interest.
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