The vast majority of environmental microbes have not yet been cultured,
and most of the knowledge on coral-associated microbes (CAMs) has been
generated from amplicon sequencing and metagenomes. However, exploring
cultured CAMs is key for a detailed and comprehensive characterization
of the roles of these microbes in shaping coral health and, ultimately,
for their biotechnological use as, for example, coral probiotics and
other natural products. Here, the strategies and technologies that have
been used to access cultured CAMs are presented, while advantages and
disadvantages associated with each of these strategies are discussed. We
highlight the existing gaps and potential improvements in
culture-dependent methodologies, indicating several possible
alternatives (including culturomics and in situ diffusion
devices) that could be applied to retrieve the CAM “dark matter” (i.e.,
the currently undescribed CAMs). This study provides the most
comprehensive synthesis of the methodologies used to recover the
cultured coral microbiome to date and draws suggestions for the
development of the next generation of CAM culturomics.