Next Article in Journal
Red and Blue Light Promote the Accumulation of Artemisinin in Artemisia annua L.
Next Article in Special Issue
Functional Characterisation of New Sesquiterpene Synthase from the Malaysian Herbal Plant, Polygonum Minus
Previous Article in Journal
Enhanced Antioxidant Activity of Bioactives in Colored Grains by Nano-Carriers in Human Lens Epithelial Cells
Previous Article in Special Issue
Multicomponent Domino Synthesis, Anticancer Activity and Molecular Modeling Simulation of Complex Dispirooxindolopyrrolidines
Article Menu
Issue 6 (June) cover image

Export Article

Open AccessArticle
Molecules 2018, 23(6), 1328;

Replacing Standard Reporters from Molecular Cloning Plasmids with Chromoproteins for Positive Clone Selection

Departamento de Biología, Universidad de Guanajuato, Noria Alta, 36050 Guanajuato, Mexico
Author to whom correspondence should be addressed.
Received: 24 April 2018 / Revised: 23 May 2018 / Accepted: 25 May 2018 / Published: 31 May 2018
(This article belongs to the Special Issue Design in Synthetic Biology)
Full-Text   |   PDF [3751 KB, uploaded 21 June 2018]   |  


Cloning and expression plasmids are the workhorses of modern molecular biology. Despite the pathway paved by synthetic biology, laboratories around the globe still relay on standard cloning techniques using plasmids with reporter proteins for positive clone selection, such as β-galactosidase alpha peptide complementation for blue/white screening or ccdB, which encodes for a toxic DNA gyrase. These reporters, when interrupted, serve as a positive clone detection system. In the present report, we show that molecular cloning plasmids bearing the coding sequence for a 25.4 kDa protein, AmilCP, encoded by a 685 bp gene, that is well expressed in Escherichia coli, render blue-purple colonies. Using this reporter protein, we developed and tested a cloning system based on the constitutive expression of the non-toxic AmilCP protein, that once interrupted, the loss of purple color serves to facilitate positive clone selection. The main advantage of this system is that is less expensive than other systems since media do not contain chromogenic markers such as X-gal, which is both expensive and cumbersome to prepare and use, or inductors such as IPTG. We also designed an inducible expression plasmid suitable for recombinant protein expression that also contains AmilCP cloning selection marker, a feature not commonly found in protein expression plasmids. The use of chromogenic reporters opens an important avenue for its application in other organisms besides E. coli for clone selection or even for mutant selection. View Full-Text
Keywords: molecular cloning; plasmid; clone selection; AmilCP chromoprotein; protein expression molecular cloning; plasmid; clone selection; AmilCP chromoprotein; protein expression

Graphical abstract

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Supplementary material


Share & Cite This Article

MDPI and ACS Style

Tafoya-Ramírez, M.D.; Padilla-Vaca, F.; Ramírez-Saldaña, A.P.; Mora-Garduño, J.D.; Rangel-Serrano, Á.; Vargas-Maya, N.I.; Herrera-Gutiérrez, L.J.; Franco, B. Replacing Standard Reporters from Molecular Cloning Plasmids with Chromoproteins for Positive Clone Selection. Molecules 2018, 23, 1328.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Molecules EISSN 1420-3049 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top