What Is Bacterial Whole Genome  denovo  Sequencing?

Bacterial whole genome de novo sequencing is a reference-free approach that reconstructs complete bacterial genomes, including chromosomes and plasmids, directly from sequencing data. It provides a high-quality genome assembly for identifying novel strains, characterizing gene functions, and exploring microbial diversity especially when no suitable reference genome is available.

How It Works

1. Long-Read Sequencing

Long-read platforms such as PacBio HiFi and Oxford Nanopore generate reads of 10–25 kb or longer, enabling accurate sequencing across repetitive and complex genomic regions.

2. denovo  Genome Assembly

Advanced assembly algorithms reconstruct the complete genome from sequencing reads without relying on a reference genome, producing highly contiguous assemblies.

3. Assembly Polishing

High-accuracy short-read sequencing is used to correct residual errors, improving base-level accuracy and overall assembly quality.

4. Genome Annotation

The assembled genome undergoes quality assessment and functional annotation to identify genes, genomic features, and biological functions, delivering data ready for downstream analysis.

Why Choose Bacterial Whole Genome  denovo  Sequencing?

Bacterial whole genome de novo sequencing enables complete, reference-free genome assembly, making it ideal for novel or genetically diverse bacterial strains. It provides accurate genome reconstruction, identifies complex genomic variations, and supports comprehensive functional analysis.

Key Benefits

• • Complete Genome Assembly – Generate high-quality chromosome and plasmid assemblies without a reference genome.
• • Comprehensive Genome Insights – Identify structural variants, functional genes, antimicrobial resistance genes, and repetitive regions.
• • Hybrid Sequencing Strategy – Combine long- and short-read sequencing for superior accuracy and assembly quality.
• • Broad Strain Compatibility – Suitable for novel, complex, and difficult-to-sequence bacterial species.

Our  denovo  Whole Genome Sequencing Services

We provide species-specific de novo genome sequencing solutions for a wide range of research applications.

• Bacterial Whole Genome  denovo  Sequencing

• - Reference-free genome assembly
• - Complete chromosome and plasmid reconstruction
• - Structural variation analysis

• Fungal Whole Genome  denovo  Sequencing

• - High-contiguity genome assembly
• - Resolution of repeat-rich genomes
• - Functional genome annotation

• Multi-Species  denovo  Whole Genome Sequencing

• - Support for diverse organisms
• - Long-read and short-read integration
• - Ideal for novel species without reference genomes

Workflow: From Sample to Results

Sample Submission

• - ≥10 μg high-quality genomic DNA
• - OD260/280: 1.8–2.0

• Library Preparation & Sequencing

• - PacBio, Oxford Nanopore, and Illumina platforms
• - Long- and short-read library construction

• Genome Assembly

• - Reference-free genome assembly
• - Hybrid error correction
• - Multi-round polishing

• Bioinformatics Analysis

• - Gene prediction and annotation
• - Resistance and virulence gene identification
• - Functional and comparative genomics

• Results Delivery

• - Quality control reports
• - Assembly statistics
• - Annotated genome files and analysis summary

Sequencing Strategy

• Library Preparation

• - Multiple insert-size libraries for optimal genome coverage
• - PCR-free workflow to minimize amplification bias
• - Rigorous quality control throughout library preparation

• Sequencing Platforms

• - PacBio HiFi – Highly accurate long reads (10–25 kb) for complete genome assembly.
• - Oxford Nanopore – Ultra-long reads for resolving complex genomic regions.
• - Illumina NovaSeq – High-depth short reads for assembly polishing and error correction.

• Recommended Coverage

• - PacBio HiFi: >100×
• - Illumina: >50×

• Quality Metrics

• - HiFi read accuracy >99.9%
• - Illumina Q30 ≥90%
• - High assembly continuity and completeness

Bioinformatics Analysis

• Standard Analysis

• - Raw data quality control
• - de novo genome assembly
• - Error correction and polishing
• - Gene prediction
• - Functional annotation (GO, KEGG, eggNOG)
• - Repeat sequence and CRISPR identification

• Advanced Analysis

• - Prophage and viral sequence prediction
• - Virulence and antimicrobial resistance gene analysis
• - CAZyme annotation
• - Transmembrane protein and signal peptide prediction
• - Comparative genomics, phylogenetic analysis, gene family clustering, and synteny analysis

Sample Requirements

Sample Submission Guidelines

• • Store samples in DNase-free, low-binding centrifuge tubes (e.g., 1.5 mL Eppendorf tubes).
• • Ship samples on ice packs for short distances or dry ice for extended transport.
• • Label each sample clearly with a unique identifier.

Applications of Bacterial Whole Genome  de novo  Sequencing

Our service supports diverse bacterial genomics research, including:

• • Antimicrobial Resistance Research – Detect resistance genes and genomic islands associated with antibiotic resistance.
• • Virulence Analysis – Investigate virulence factors and their evolutionary dynamics.
• • Industrial Microbiology – Identify metabolic genes for strain improvement and enhanced production.
• • Environmental Microbiology – Explore genetic adaptations that enable survival in diverse environments.
• • Novel Species Discovery – Generate complete genomes for microbial classification and taxonomic studies.

Why Choose N2Jenomics Lab Pvt. Ltd.?

• Integrated Sequencing Technologies

Leverage PacBio HiFi, Oxford Nanopore, and Illumina platforms for accurate and high-quality genome assemblies.

• Optimized Assembly Pipeline

Customized assembly workflows with hybrid error correction ensure highly accurate and complete genome reconstruction.

• Comprehensive Bioinformatics

End-to-end analysis including genome assembly, annotation, comparative genomics, resistance and virulence profiling, and pathway analysis.

• Stringent Quality Control

Standardized quality checks at every stage—from sample processing to final data delivery—for reliable and reproducible results.

• Publication-Ready Reports

Receive clear reports with assembly statistics, visual summaries, and annotated datasets for downstream analysis and publication.

• Expert Technical Support

Our genomics specialists provide guidance on experimental design, data interpretation, and post-analysis support throughout your project.

1. How is the quality of a bacterial genome assembly evaluated?

Assembly quality is typically assessed using metrics such as N50, genome completeness, number of scaffolds/contigs, GC content, ambiguous bases (N%), and total assembled genome size.

2. Can a gap-free bacterial genome assembly be achieved?

Yes. By combining long-read sequencing (PacBio HiFi or Oxford Nanopore) with short-read polishing (Illumina), most bacterial genomes can be assembled into highly complete, near gap-free sequences. Additional validation can be performed when required.

3. Is long-read sequencing alone sufficient for complete bacterial genome assembly?

Long-read sequencing provides excellent genome continuity, but combining it with high-accuracy short-read data improves base-level accuracy and helps recover small plasmids or challenging genomic regions.

4. How is assembly accuracy ensured?

Assembly accuracy is enhanced through a multi-step workflow that includes long-read error correction, de novo genome assembly, iterative polishing, and final refinement using high-quality short-read sequencing. This approach delivers highly accurate genome assemblies.

5. How do long reads improve assembly of repetitive regions?

Long reads can span repetitive DNA sequences that are difficult to resolve with short-read technologies, resulting in more contiguous assemblies and improved reconstruction of complex genomic regions.

6. Can DNA methylation be analyzed during sequencing?

Yes. PacBio HiFi sequencing can directly detect DNA base modifications, such as 6mA and 4mC, without requiring additional library preparation or separate sequencing experiments.

7. Does extreme GC content affect sequencing quality?

Modern long-read sequencing platforms are designed to minimize GC bias, providing consistent genome coverage across both GC-rich and GC-poor bacterial genomes for reliable assembly results.