Cloned Fragments for custom DNA cloning vector


Cloned Fragments

Save time manual cloning with custom gene cloning of inserts up to 7.5kbp. 

Pick from a library of application-ready, public backbones, or use your own and store your vectors with us for easy reuse.

From €0.12 /bp

Custom gene cloning for faster research

Doulix custom gene cloning provides assembly and expression ready vectors of unparalleled quality, length and complexity. Order 100% sequence perfect clones with ease and we’ll do the rest, from optimisation to preparation.

  • Inserts of 0.25kbp – 7.5kbp
  • >80% and < 20% GC content
  • Complexity as standard
  • from €0.12 /bp

Comprehensive optimisation of your inserts is as standard for all of Doulix single gene constructs.

Our AI algorithm, trained on thousands of real world experiments computes multiple factors to optimise assembly, codons, gene expression and more.

  • Scarless assembly optimisation.
  • Troubleshooting as standard.
  • Successful optimisation of high number of repeats per sequence.

All Doulix cloning vectors are 100% sequenced verified with Sanger sequencing and produced to our rigorous laboratory procedures according ISO 9001:2008 standards.

  • 100% sanger sequence verified.
  • ISO 9001:2008 certified production standards.
  • Doulix Quality promise or your money back.

Average turnaround for custom cloning vectors is 21 days and getting faster. Of course, depending on complexity TAT may vary accordingly. We estimate delivery during checkout and then keep you up to date in real-time. 

With a greater than 90% as promised delivery, you can be confident your samples will be arriving when we say so. That way you’re ready to start research the moment your samples arrive.

  • Avg. turnaround 21 days
  • Lyophilized DNA options in a range of prep sizes (1 ug, 10 ug, 50 ug, 5 mg)
  • E. coli stab agar and glycerol stock delivery options.
  • Add ons available for one stop shopping
  • Customs and shipping handling included.

Which backbone?

Standard subcloning from €42.  Free options available.

It’s your choice. You can send us your own custom backbone. 

Or you can save some time on design. Pick from the largest library of lab-tested vectors designed for purpose by pro laboratories. 

Doulix offers free sub-cloning into a number of lab-tested vector backbones.

BackboneSuitable forDescription
pSEVA-18 Linear backboneE. coliLinear vector backbone obtained by digesting pSEVA181 with PacI and SpeI restriction enzyme.
pDLX_3A100E. coliMedium copy number plasmid compatible with DNAmate assembly, containing an Amp resistance gene and the p15A origin of replication. The backbone contains IIs restriction sites for use in cloning techniques based on Golden Gate, such as DNAmate and MoClo
pSB1C3 BackboneE. coliHigh copy number plasmid carrying CPL resistance. The replication origin is a pUC19-derived pMB1 (copy number of 100-300 per cell). The terminators bracketing its MCS are designed to prevent transcription from inside the MCS from reading out into the vector

Doulix is an official partner of the initiative for Standard European Vector Architecture (SEVA)Our pSEVA constructs and biomodules are rigorously tested and widely used, ensuring quality and functional.

BackboneSuitable forDescription
pSEVA-18 Linear backboneE. colilinear vector backbone obtained by digesting pSEVA181 with PacI and SpeI restriction enzyme.
pSEVA_27 Linear BackboneE. coliThis biomodule encodes for the linear vector backbone obtained by digesting pSEVA271 with PacI and SpeI restriction enzyme.
pSEVA_181 Linear BackboneE. coliThis backbone is meant to be used to subclone custom genes as cargo between PacI and SpeI restriction sites

We host a vast catalogue of fully-verified backbones created by top the world’s top laboratories for use with E.coli.

Explore the full catalogue of E. coli backbones.

BackboneSuitable forDescription
pET-15b plasmidE. coliThe biomodule carries the backbone of pET-15b plasmid with an Amp resistance gene, a pBR322 replicon and a gene coding for LacI repressor. The biomodule is part of pET plasmids used in combination with an E. coli strain carrying the T7 RNA polymerase gene. pET plasmids and parts thereof were developed by Novagen and are available for Research Use Only.
pDLX_1k2E. coliBackbone of a high copy number plasmid compatible with DNAmate assembly, containing a Kan resistance gene and the origin of replication from pUC plasmids.
CIDAR DVA BackboneE. coliBackbone derived from DVA and harbors 2 BsaI restriction sites for Goldengate assembly. DVA is meant for Level 0 CIDAR constructs carrying individual Biomodule. DVA derives from pSB1A2. High copy number plasmid carrying Amp resistance. The replication origin is a pUC19-derived pMB1 (copy number of 100-300 per cell). All Biomodules of the CIDAR collection were designed by the Densmore Lab at the Boston University and are provided as they are and solely for research purpose. [Iverson et al., ACS Synthetic Biology, 2015]
BackboneSuitable forDescription
pcDNA3.1 BackboneMammalHigh-level stable and non-replicative transient expression for most mammalian cells. The vector contains the following elements: human cytomegalovirus immediate-early (CMV) promoter for high-level expression in a wide range of mammalian cells; neo resistance gene for selection of stable cell lines; episomal replication in cells lines that are latently infected with SV40 or that express the SV40 large T antigen (e.g. COS-1, COS-7). pCDNA3.1 was developed by Invitrogen Corporation and is available free of charge for Research Use Only. Not for use in diagnostic procedures.
BackboneSuitable forDescription
Gateway pDEST 26 derivateMammal, insect, yeast, E.coliInvitrogen offers state-of-the-art Gateway destination vectors for expression in E. coli, insect, yeast, or mammalian cells, as well as for production of native protein or N- or C-terminal fusion proteins. All Gateway destination vectors have attR sites for recombination with any attL-flanked fragment, regardless of whether it is an entry clone or an Ultimate RF Clone. The following table lists the wide range of destination vectors available.
pEAQ_backbonePlants, yeast, E.colipEAQ_backbone derivates from Agrobacterium tumefaciens Ti plasmid and is meant to carry the cargo to be transfected to the plant host. It contains the left border (LB) and right border (RB) short direct repeats required to initiate the transfer. In addition, it contains ORI and selection markers for effective use in multiple hosts.

Import your plasmid of choice to DOULIX by uploading the FASTA file format and start immediately to work on it. Your FASTA will be used to generate a fully customizable construct that you can edit and optimise using our browser based bioCAD

Once complete, send us your custom vector backbone and we’ll subclone your fragments in to it. Easy

for high-throughput vector workflows


hours of manual cloning saved

Concentrate on what counts

Skip manual gene cloning and jump straight to assembly or expression. Our custom gene cloning can save you hundreds of hours per year manually cloning.


sequence perfect

Quality Assured

Start research confident of the quality of your vectors. Every cloned fragment is 100% sanger sequence verified and comes with Doulix quality promise.


delivery in 2020

Success as standard

Start a project with Doulix and you’ll finish it with us too. Our near perfect delivery rates mean you know we won’t let you down.

dsDNA Fragments

Custom Constructs


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So yeah sure, you can keep thinking those experiments are impossible. Or you can challenge us with your toughest requests for none of the risk.