Effects of illumination on bacterial communities in symbiotic amphibian egg masses

The salamander Ambystoma maculatum hosts the symbiotic green alga Oophila amblystomatis in its egg capsules. But the egg capsules are colonized by other microbes, including bacteria, that may be important in this special community ecology. We split three egg masses in half, and reared half of each mass in illuminated or a darkened conditions, thus preventing algal growth. We subjected egg capsular fluid from the two conditions to 16S rRNA gene amplicon sequencing (V4-V5 region).