Pyrosequencing technology, which is based on the principle of sequencing by synthesis, provides quantitative data in sequence context within minutes. PyroMark Q96 ID is a fully integrated system that provides real-time sequence information and is highly suitable for detection of genetic variations, genetic quantification, and short DNA sequencing. The following products are used in combination with PyroMark Q96 ID instrument: PyroMark Q96 Vacuum Workstation, PyroMark CpG SW, PyroMark Assay Design SW, PyroMark IdentiFire SW, PyroMark Gold Q96 Reagents, and PyroMark Control Oligo. Sample preparation solutions are also supplied to enable preparation of single-stranded DNA using the PyroMark Q96 Vacuum Workstation.
Steps of the Pyrosequencing reaction:
Step 1: A DNA segment is amplified, and the strand to serve as the Pyrosequencing template is biotinylated. After denaturation, the biotinylated single-stranded PCR amplicon is isolated and allowed to hybridize with a sequencing primer. The hybridized primer and single-stranded template are incubated with the enzymes DNA polymerase, ATP sulfurylase, luciferase, and apyrase, as well as the substrates adenosine 5' phosphosulfate (APS) and luciferin (see figure " Principle of Pyrosequencing — step 1").
Step 2: The first deoxribonucleotide triphosphate (dNTP) is added to the reaction. DNA polymerase catalyzes the addition of the dNTP to the squencing primer, if it is complementary to the base in the template strand. Each incorporation event is accompanied by release of pyrophosphate (PPi), in a quantity equimolar to the amount of incorporated nucleotide (see figure " Principle of Pyrosequencing — step 2").
Step 3: ATP sulfurylase converts PPi to ATP in the presence of adenosine 5' phosphosulfate (APS). This ATP drives the luciferase-mediated conversion of luciferin to oxyluciferin that generates visible light in amounts that are proportional to the amount of ATP. The light produced in the luciferase-catalyzed reaction is detected by CCD sensors and seen as a peak in the raw data output (Pyrogram). The height of each peak (light signal) is proportional to the number of nucleotides incorporated (see figure " Principle of Pyrosequencing — step 3").
Step 4: Apyrase, a nucleotide-degrading enzyme, continuously degrades unincorporated nucleotides and ATP. When degradation is complete, another nucleotide is added (see figure " Principle of Pyrosequencing — step 4").
Step 5: Addition of dNTPs is performed sequentially. It should be noted that deoxyadenosine alpha-thio triphosphate (dATPαS) is used as a substitute for the natural deoxyadenosine triphosphate (dATP), since it is efficiently used by the DNA polymerase, but not recognized by the luciferase. As the process continues, the complementary DNA strand is elongated, and the nucleotide sequence is determined from the signal peaks in the Pyrogram trace (see figure " Principle of Pyrosequencing — step 5").
Streamlined workflow — from sample to result
The versatile PyroMark Q96 ID seamlessly integrates into epigenetics and genetic analysis workflows, and complements QIAGEN's advanced technologies for sample preparation, bisulfite conversion, and PCR amplification. This highly reliable instrument enables sequence-based quantification and detection of SNPs, insertion and deletion mutations, CpG sites, as well as generation of sequence information. The streamlined workflow means that results can be achieved faster.
Fast and easy sample preparation
From PCR product to single-stranded template ready for sequencing — up to 96 samples can be prepared in parallel using the PyroMark Q96 Vacuum Workstation, in less than 15 minutes. The workstation ensures easy handling and the actual "hands-on time" is less than 5 minutes.