Community composition of the Planctomycetes associated with different macroalgae

Area of Science:

• Marine microbiology
• Molecular ecology
• Biofilm research

Background:

• Marine macroalgae host diverse microbial biofilms.
• Planctomycetes are often dominant in these epibacterial communities.
• Understanding microbial specificity is crucial for marine ecosystem studies.

Purpose of the Study:

• To investigate the diversity and specificity of Planctomycetes communities on six different macroalgae species.
• To assess the influence of algal host and geographical location on Planctomycetes community structure.
• To determine the degree of host specificity for Planctomycetes associated with macroalgae.

Main Methods:

• Application of denaturing gradient gel electrophoresis (DGGE) targeting 16S rRNA genes specific to Planctomycetes.
• Comparison of Planctomycetes communities from six macroalgae species sampled from two locations in Northern Portugal.
• Analysis of Shannon diversity indexes and anosim statistics to evaluate community structure and specificity.
• Sequencing of DGGE bands to identify specific Operational Taxonomic Units (OTUs).

Main Results:

• Shannon diversity indexes for Planctomycetes were generally similar across macroalgae and sites.
• Fucus spiralis exhibited lower Planctomycetes diversity, while Mastocarpus stellatus and Porphyra dioica showed higher diversity.
• Statistical analysis indicated a specific Planctomycetes community associated with the algal host, independent of geographical variation.
• Sequencing revealed high diversity within Planctomycetes communities, with some OTUs showing association with specific macroalgae.

Conclusions:

• Marine macroalgae harbor distinct Planctomycetes communities.
• Planctomycetes community composition is significantly influenced by the algal host.
• Geographical location had a limited impact on the specificity of Planctomycetes communities.
• The findings highlight the potential for host-specific microbial associations in marine biofilms.