Olive replicate 2
DNA was extracted by the DNeasy PowerBiofilm Kit (Qiagen, Germany) with FastPrep-24 homogenizer (MP Biomedicals, USA) according to the protocol provided by the manufacturer. The amount of DNA was assessed using Qubit (Invitrogen, USA) and Qubit dsDNA High Sensitivity Kit (Invitrogen, USA). Bacterial V4 variable regions of the 16S rRNA genes were amplified with the universal primers 515F (5'-GTGCCAGCMGCCGCGGTAA-3') and 806R (5'-GGACTACHVGGGTWTCTAAT-3'). Each 806R primer contained different barcodes.Sequencing was performed using Illumina MiSeq platform and MiSeq Reagent Kit V2 2250 bp (Illumina) according to the Illumina workflow (Illumina protocol, Part #15044223, Rev. B).