292
14.5 Conclusion
Bacteria and algae have a diverse range of possible interactions, some of which have
been well studied and reviewed for macroalgae (Egan et al. 2013, 2014; Singh and
Reddy 2014) and microalgae (Mayali and Azam 2004; Azam and Malfatti 2007;
Geng and Belas 2010; Natrah et al. 2014; Ramanan et al. 2016). However, the identity of the causative bioactive compound specific to each interaction has often not
been elucidated. Some research has been done on understanding the chemical signalling between algal species and within populations (Legrand et al. 2003;
Borowitzka 2016), interactions with algae and their predators (Tillmann 2004;
Pohnert et al. 2007), but less is known about the chemical underpinnings of the
algal-bacterial interactions (Demuez et al. 2015; Hom et al. 2015). Understanding
the cross talk between the algal host and their bacterial symbionts allows us to better
understand and manipulate the environment.
More research is needed on how the various organisms communicate with each
other in a complex community rather than the regulated (and often one-on-one) cocultures regularly studied in the lab. More complex communities will have beneficial and
harmful interactions occurring between various organisms within the community,
which will not be encompassed by a single model system. Further complicating the
system, some bacteria may break down products produced by other members of the
community, which will have novel impacts on the system being studied. As a final
level of complexity, the environmental conditions may affect the interactions (Grossart
1999). Small-scale systems can be used to successfully monitor long-term interactions between microalgae and bacteria (Bramucci et al. 2015). However, translating
the micro-scale experiments into larger scales is also an important field that needs
further work, as the larger scales can affect the algal characteristics, as the turbulence,
light penetration, nutrient availability and the bacterial assemblage present become
less homogenous, and this heterogeneity can make extrapolations difficult from
smaller scale (Grossart 1999; Sing et al. 2013; Lohrer et al. 2015). While recent
advances in omics reveal a new level of detail in our understanding in microbial ecology (Jansson et al. 2012; Cooper and Smith 2015), they can be used in conjunction
with lab systems or to better inform new hypothesizes for new experiments (Amin
et al. 2015; Hom et al. 2015). As researchers continue to probe into the underlying
novel functions of bioactive molecules, it is likely that even more new insights about
their complex roles in shaping and controlling microbial communities will arise.
Acknowledgement This work was supported by Natural Sciences and Engineering Research
Council of Canada (grant 402105) to RJC.
References
Amaro AM, Fuentes MS, Ogalde SR et al (2005) Identification and characterization of potentially algal-lytic marine bacteria strongly associated with the toxic dinoflagellate Alexandrium
catenella. J Eukaryot Microbiol 52:191–200
L. Labeeuw et al.
14.5 Conclusion
Bacteria and algae have a diverse range of possible interactions, some of which have
been well studied and reviewed for macroalgae (Egan et al. 2013, 2014; Singh and
Reddy 2014) and microalgae (Mayali and Azam 2004; Azam and Malfatti 2007;
Geng and Belas 2010; Natrah et al. 2014; Ramanan et al. 2016). However, the identity of the causative bioactive compound specific to each interaction has often not
been elucidated. Some research has been done on understanding the chemical signalling between algal species and within populations (Legrand et al. 2003;
Borowitzka 2016), interactions with algae and their predators (Tillmann 2004;
Pohnert et al. 2007), but less is known about the chemical underpinnings of the
algal-bacterial interactions (Demuez et al. 2015; Hom et al. 2015). Understanding
the cross talk between the algal host and their bacterial symbionts allows us to better
understand and manipulate the environment.
More research is needed on how the various organisms communicate with each
other in a complex community rather than the regulated (and often one-on-one) cocultures regularly studied in the lab. More complex communities will have beneficial and
harmful interactions occurring between various organisms within the community,
which will not be encompassed by a single model system. Further complicating the
system, some bacteria may break down products produced by other members of the
community, which will have novel impacts on the system being studied. As a final
level of complexity, the environmental conditions may affect the interactions (Grossart
1999). Small-scale systems can be used to successfully monitor long-term interactions between microalgae and bacteria (Bramucci et al. 2015). However, translating
the micro-scale experiments into larger scales is also an important field that needs
further work, as the larger scales can affect the algal characteristics, as the turbulence,
light penetration, nutrient availability and the bacterial assemblage present become
less homogenous, and this heterogeneity can make extrapolations difficult from
smaller scale (Grossart 1999; Sing et al. 2013; Lohrer et al. 2015). While recent
advances in omics reveal a new level of detail in our understanding in microbial ecology (Jansson et al. 2012; Cooper and Smith 2015), they can be used in conjunction
with lab systems or to better inform new hypothesizes for new experiments (Amin
et al. 2015; Hom et al. 2015). As researchers continue to probe into the underlying
novel functions of bioactive molecules, it is likely that even more new insights about
their complex roles in shaping and controlling microbial communities will arise.
Acknowledgement This work was supported by Natural Sciences and Engineering Research
Council of Canada (grant 402105) to RJC.
References
Amaro AM, Fuentes MS, Ogalde SR et al (2005) Identification and characterization of potentially algal-lytic marine bacteria strongly associated with the toxic dinoflagellate Alexandrium
catenella. J Eukaryot Microbiol 52:191–200
L. Labeeuw et al.