Construction of Fluorescent Analogs to Follow the Uptake and Distribution of Cobalamin (Vitamin B12) in Bacteria, Worms, and Plants

Jul 6, 2026

Vitamin B12 is synthesized by specific prokaryotes but required by many eukaryotes across diverse lineages, and how this nutrient traffics between domains of life remains incompletely understood. The work constructs corrin and ribose-site cobalamin analogs bearing fluorescent groups to enable visualization. Fluorescent derivatives reveal organism-specific uptake: Mycobacterium tuberculosis can acquire cobyric acid and cobalamin analogs, Caenorhabditis elegans preferentially takes up only complete corrinoids, and higher-plant seedlings such as Lepidium sativum can transport B12.

LanguageEnglish

CategoryResearch & Report

FormatPDF

Pages28

Reading Time1 h 11 min

Summary

Fluorescent analog design

Uptake in bacteria, worms, and plants

Introduction

Diversity of cobamides and B12 forms

Article Construction of Fluorescent Analogs to Follow the Uptake and Distribution of Cobalamin (Vitamin B 12)in Bacteria, Worms, and Plants Authors Andrew D. Lawrence, Emi Nemoto-Smith, Evelyne Deery, ..., Helena I. Boshoff, Clifton E. Barry III, Martin J. Warren Correspondence [m.j.warren@kent.ac.uk](m.j.warren@kent.ac.uk) In Brief Lawrence et al., employed chemical biology approaches to construct a range of ﬂuorescent vitamin B12 derivatives. They demonstrated that these ﬂuorescent variants can be used to follow intracellular B12 trafﬁcking in bacteria, including E. coli and M. tuberculosis, the worm C. elegans, and a higher plant (Lepidium sativum) . d SAM analogs have been used to make variants of vitamin B12 d Analogs of B12 with ﬂuorescent groups attached to the corrin ring are described d The uptake of B12 analogs into E. coli and M. tuberculosis is shown d Vitamin B12 analogs are shown to accumulate in worms and higher plants Lawrence et al., 2018, Cell Chemical Biology 25, 941–951 August 16, 2018 ª 2018 Elsevier Ltd. [https://doi.org/10.1016/j.chembiol.2018.04.012](https://doi.org/10.1016/j.chembiol.2018.04.012) Cell Chemical Biology Article Construction of Fluorescent Analogs to Follow the Uptake and Distribution of Cobalamin (Vitamin B12) in Bacteria, Worms, and Plants Andrew D. Lawrence,1,4 Emi Nemoto-Smith,1,2,4 Evelyne Deery,1 Joseph A. Baker,1 Susanne Schroeder,1 David G. Brown,1 Jennifer M.A. Tullet,1 Mark J. Howard,1 Ian R. Brown,1 Alison G. Smith,3 Helena I. Boshoff,2 Clifton E. Barry III,2 and Martin J. Warren1,5,* 1School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, UK 2National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20850, USA 3Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK 4These authors contributed equally 5Lead Contact *[Correspondence: m.j.warren@kent.ac.uk](Correspondence: m.j.warren@kent.ac.uk) [https://doi.org/10.1016/j.chembiol.2018.04.012](https://doi.org/10.1016/j.chembiol.2018.04.012) SUMMARY Vitamin B12 is made by only certain prokaryotes yet is required by a number of eukaryotes such as mammals, ﬁsh, birds, worms, and Protista, including algae. There is still much to learn about how this nutrient is trafﬁcked across the domains of life. Herein, we describe ways to make a number of different corrin analogs with ﬂuorescent groups attached to the main tetrapyrrole-derived ring. A further range of analogs were also constructed by attaching similar ﬂuorescent groups to the ribose ring of cobalamin, thereby generating a range of complete and incomplete corrinoids to follow uptake in bacteria, worms, and plants. By using these ﬂuorescent derivatives we were able to demonstrate that Mycobacterium tuberculosis is able to acquire both cobyric acid and cobalamin analogs, that Caenorhabditis elegans takes up only the complete corrinoid, and that seedlings of higher plants such as Lepidium sativum are also able to transport B12. INTRODUCTION The cobamides encompass a group of closely structurally related nutrients, cofactors, and coenzymes that harbor a cobalt-containing corrin ring, and are often loosely referred to as vitamin B12 (Figure 1)(Renz, 1999; Warren et al., 2002) . These molecules vary in the nature of the upper ligand attached to the cobalt and the character of the lower nucleotide loop. Cobalamin, for instance, contains dimethylbenzimidazole as the base in the nucleotide loop but this is replaced with adenine in pseudocobalamin (Figure 1) (Degnan et al., 2014; Maggio-Halland Escalante-Semerena, 2003) . In the biologically active forms of cobalamin the cobalt ion is normally either adenosylated (adenosylcobalamin) or methylated (methylcobalamin) (Banerjee and Ragsdale, 2003), while vitamin B12 represents the cyano- lated derivative of cobalamin that is produced during the commercial extraction and isolation of the nutrient

FAQs

What is the goal of constructing fluorescent B12 analogs in this study?

To create corrin- and ribose-derived fluorescent cobalamin analogs that enable tracking B12 uptake and distribution in different organisms.

Which organisms are used to evaluate fluorescent B12 analog uptake?

The study examines bacteria including E. coli and Mycobacterium tuberculosis, the worm Caenorhabditis elegans, and the higher plant Lepidium sativum.

What uptake differences are reported for Mycobacterium tuberculosis versus C. elegans?

Mycobacterium tuberculosis can acquire both cobyric acid and cobalamin analogs, while C. elegans takes up only complete corrinoids.

Jul 6, 2026

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