Halobates guts
Bacterial libraries were prepared following a two-step dual-indexing approach, following the instructions provided by Illumina. The V3-V4 hypervariable region of the bacterial 16S ribosomal RNA (rRNA) gene was amplified using the primers 341f and 785r [26]. The polymerase chain reaction (PCR) master mix consisted of 1 buffer, 1.5 mM MgCl2, 0.3 mM dNTPs, 0.3 mM of each primer, 1 U HiFi Platinum Taq (Invitrogen), and 3-5 L of DNA. The products obtained were amplified using the Nextera XT Index kit (Illumina, Inc.) to tag each sample uniquely; the final products were cleaned using SequalPrepTM Normalization Plate (96-well) kit. The quality and size of the final library were evaluated by automated electrophoresis using the Bioanalyzer (Agilent Technologies, Inc.). DNA within libraries was quantified by using KAPA Library Quantification kits (Illumina, Inc.), ensuring an accurate qPCR-based quantification. Libraries were sequenced on an Illumina MiSeq platform (V3, 300 bp paired-end) at the Bioscience Core Lab (BCL) of King Abdullah University of Science and Technology (KAUST).