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DeLiberto, A.

Publications and source records attributed to DeLiberto, A..

2 recordsLinked to original sources

A novel NGS-compatible Enzymatic Strategy Enables Carryover Contamination Removal and Enhances Sequencing Performance.

Carryover contamination during DNA amplification can often lead to false positives. Traditional mitigation strategies often include physical separation and/or enzymatic decontamination. However, these methods have limitations, including logistical constraints and polymerase compatibility issues especially for Next Generation Sequencing (NGS). Here, we introduce a novel approach using 7-deaza-dGTP and Fpg for carryover amplicon degradation. When incorporated into library preparation, Fpg degrades 7-deaza-deoxyguanosine amplicons providing carryover protection comparable to the established dUTP/UDG strategy with over 95% carryover contamination removal. Unlike currently available carryover enzyme/dNTP solutions, 7-deaza-deoxyguanosine is compatible with many polymerases and does not impact substitution frequencies during sequencing. Additionally, due to its chemical properties, incorporating 7-deaza-dGTP during amplification improves GC bias during sequencing. In turn, this method is compatible with NGS, supports broader polymerase compatibility, and improves sequencing performance, particularly in AT- and GC-rich regions.

genomics↗

The discovery of 5mC-selective deaminases and their application to ultra-sensitive direct sequencing of methylated sites at base resolution.

Mining phages for new enzymatic activities continues to be important for the development of new tools for biotechnology. In this study, we used MetaGPA--a method linking genotype to phenotype in metagenomic data--to identify deoxycytidine deaminases, a protein family highly associated with cytosine modifications in metaviromes. Unexpectedly, a subset of these deaminases exhibited a preference for 5-methylcytosine (5mC) over cytosine (C) in both mononucleotide and single-stranded DNA substrates. In a methylome sequencing workflow, preferential deamination of 5mC by these enzymes enabled direct conversion of methylated cytosine while completely eliminating any background deamination of unmodified cytosine. This direct conversion allows for precise identification of methylated sites at single-base resolution with unmatched sensitivity enabling broad applications for the simultaneous sequencing of genome and methylome.

genomics↗