Dr Adam Roberts

Reader, Antimicrobial Chemotherapy and Resistance

Graduated in Applied Biology from Coventry University in 1995 and with a PhD from the University of London in 2002. Worked as a Post-Doctoral Research Fellow, Lecturer and Senior Lecturer at the Eastman Dental Institute, University College London until joining the LSTM in February 2017.

My research activities have focussed on transferable antimicrobial resistance (AMR) and mobile genetic elements in human associated metagenomes and various pathogens including Clostridium difficile, Streptococcus spp., Enterococcus spp., Klebsiella pneumoniae and Escherichia coli.


Biological consequences of acquisition of AMR within the Enterobacteriaceae; Acquisition of resistance can carry a biological cost which can reduce the fitness of the hosts. We are looking at ways of maximising this biological cost in order to minimise the persistence of resistance once a selection pressure is removed. We are aiming to be able to inform clinicians of treatment regimens which will do exactly this when multi-drug resistance occurs.

Molecular biology of mobile genetic elements Mobile genetic elements are responsible for the dissemination of AMR. We are working towards understanding the molecular mechanisms which govern both intra- and intercellular mobility with a translational focus of using this knowledge to prevent their spread and also use them as tools in order to reduce AMR.

Antimicrobial Drug Discovery In order to tackle the increasing lack of available antibiotic we need new drugs. We have a citizen science project; “Swab and Send” that aims to search for these whilst at the same time engaging public, schools and other groups about the issues surrounding AMR. We are currently working on novel environmental isolates which can produce compounds capable of inhibiting the growth of drug resistant Enterobacteriaceae and Candida albicans. 

Member Microbiology Society, Society of Applied Microbiology, Royal Society of Biology, British Society for Antimicrobial Chemotherapy.

Fellow Higher Education Academy

Advisor Longitude Prize

Selected public engagement activities

Swab and Send; https://www.facebook.com/swabandsend/

Advisor Surgeon X; http://surgeonx.co.uk/ 

Advisor Superbugs; https://longitudeprize.org/superbugs

Advisor Antibiotic Apocalypse; http://gamedrlimited.com/antibiotic-apocalypse/

Selected publications

  • S Tansirichaiya, P Mullany, AP Roberts. (2016). PCR-based detection of composite transposons and translocatable units from oral metagenomic DNA. FEMS Microbiol Lett. 363(18). pii: fnw195. doi: 10.1093/femsle/fnw195.

    PJ Warburton, N Amodeo, AP Roberts. (2016). Mosaic tetracycline resistance genes encoding ribosomal protection proteins. J Antimicrob Chemother. 71(12):3333-3339

    MS Brouwer, P Mullany, E Allan, AP Roberts. (2016) Investigating Transfer of Large Chromosomal Regions Containing the Pathogenicity Locus Between Clostridium difficile Strains. Methods Mol Biol. 2016;1476:215-22.

    LJ Reynolds, AP Roberts, MF Anjum. (2016) Efflux in the Oral Metagenome: The Discovery of a Novel Tetracycline and Tigecycline ABC Transporter. Front Microbiol. 7:1923. doi: 10.3389/fmicb.2016.01923.

    C Novais, AP Tedim, VF Lanza, AR Freitas, E Silveira, R Escada, AP Roberts, M Al-Haroni, F Baquero, L Peixe, TM Coque. (2016) Co-diversification of Enterococcus faecium Core Genomes and PBP5: Evidences of pbp5 Horizontal Transfer. Front Microbiol. doi: 10.3389/fmicb.2016.01581

    S Tansirichaiya, MA Rahman, A Antepowicz, P Mullany, AP Roberts (2016) Detection of Novel Integrons in the Metagenome of Human Saliva. PLoS One. 11(6):e0157605. doi: 10.1371/journal.pone.0157605

    E Eijk, SY Anvar, HP Browne, WY Leung, J Frank, AM Schmitz, AP Roberts, WK Smits. (2015). Complete genome sequence of the Clostridium difficile laboratory strain 630Derm reveals translocation of the mobile element CTn5. BMC Genomics16(1):31.

    H Browne, SY Anvar, J Frank, T Lawley, AP Roberts, WK Smits, (2015) Complete genome sequence of BS49 and draft genome sequence of BS34A, Bacillus subtilis strains carrying Tn916. FEMS Microbiology Letters 362:1-4

    C Lena, MSM Brouwer, P. Mullany AP Roberts (2014) Minocycline resistance in an oral Streptococcus infantis isolate is encoded by tet(S) on a novel small, low copy number plasmid. FEMS Microbiology Letters. 353:106-115.

    M Seier-Petersen, A Jasni, F Aarestrup, H Vigre, P Mullany, AP Roberts Y Agersø. (2014) Effect of sub-inhibitory concentrations of four commonly used biocides on the conjugative transfer of Tn916 in Bacillus subtilis. Journal of Antimicrobial Chemotherapy. 69(2):343-8.

    I Starikova, M Al-Haroni, G Werner, AP Roberts, V Sørum, KM Nielsen, PJ Johnsen. (2013) Fitness costs of various mobile genetic elements in Enterococcus faecium and Enterococcus faecalis. Journal of Antimicrobial Chemotherapy. 68(12):2755-65.

    MSM Brouwer, AP Roberts, H Hussain, RW Williams, E Allan, P Mullany. (2013) Horizontal gene transfer converts non-toxigenic Clostridium difficile to toxin producers. Nature Communications. doi:10.1038/ncomms3601.

    R Williams, E Meader, M Mayer, A Narbad, AP Roberts and P Mullany. (2013) Determination of the attP and attB sites of phage φCD27 from Clostridium difficile NCTC 12727. Journal of Medical Microbiology. 62; 1439-1443.

    X Song, J Sun, T Mikalsen, AP Roberts, A Sundsfjord. (2013) Characterisation of the plasmidome within Enterococcus faecalis isolated from marginal periodontitis patients in Norway. PLoS One. 8(4): e62248. doi:10.1371/journal.pone.0062248

    P Warburton, L Ciric, A Lerner, L Seville, AP Roberts, Peter Mullany, Elaine Allan. (2013) TetAB(46), a predicted heterodimeric ABC transporter conferring tetracycline resistance in Streptococcus australis isolated from the oral cavity. Journal of Antimicrobial Chemotherapy. 68: 17-22.

    V Zidaric, B Pardon, T Vultos, P Deprez, M Brouwer, AP Roberts, Adriano Henriques, and Maja Rupnik. (2012) Multiclonal presence of Clostridium difficile PCR ribotypes 078, 126 and 033 within a single calf farm is associated with differences in antibiotic resistance and sporulation properties. Applied and Environmental Microbiology. 78: 8515-22

    C Novais, AR. Freitas, E Silveira, F Baquero, L Peixe, AP Roberts, Teresa M. Coque. (2012) A tet(S/M) hybrid from CTn6000 and CTn916 recombination. Microbiology. 158: 2710-1.

    C Novais, AR Freitas, E Silveira, F Baquero, L Peixe, AP Roberts, and Teresa Coque. (2012) Different genetic supports for the tet(S) gene in enterococci. Antimicrob Agents and Chemotherapy. 56(11): 6014-8.

    J Corven, D Bakker , M Brouwer , C Harmanus , MP Hensgens , AP Roberts , Ed J Kuijper , Hans C van Leeuwen. (2012) Analysis of a Clostridium difficile PCR ribotype 078 100 kilobase island reveals the presence of a novel transposon; Tn6164. BMC Microbiology. 12:130. doi: 10.1186/1471-2180-12-130

    MSM Brouwer, E Allan, P Mullany, AP Roberts, (2012) Draft genome sequence of the non-toxigenic Clostridium difficile strain CD37. Journal of Bacteriology. 194; 2125-6.

    L Ciric, M Ellatif, P Sharma, R Patel, X Song, P Mullany, AP Roberts. (2012) Tn916-like elements from human, oral, commensal streptococci possess a variety of antibiotic and antiseptic resistance genes. International Journal of Antimicrobial Agents. 39; 360-361.

    P Mullany, R Williams, GC Langridge, DJ. Turner, R Whalan, C Clayton, T Lawley, H Hussain, K McCurrie, N Morden, E Allan, AP Roberts. (2012) Behaviour and target site selection of the conjugative transposon Tn916 in two different strains of toxigenic Clostridium difficile. Applied and Environmental Microbiology. 78; 2147-53

    MSM Brouwer, AP Roberts, P Mullany, E Allan. (2012) In silico analysis of sequenced strains of C. difficile reveals a related set of conjugative transposons carrying a variety of accessory genes. Mobile Genetic Elements.2; 8-12.

    L Ciric, P Mullany, AP Roberts. (2011) Antibiotic and antiseptic resistance genes are linked on a novel mobile genetic element: Tn6087. Journal of Antimicrobial Chemotherapy. 66; 2235-9.

    MSM Brouwer, PJ Warburton, AP Roberts, P Mullany, E Allan. (2011) Genetic Organisation, Mobility and Predicted Functions of Genes on Integrated, Mobile Genetic Elements in Sequenced Strains of Clostridium difficile. PLoS ONE 6(8): e23014. doi:10.1371/journal.pone.0023014

    G Rossi-Fedele, JAP de Figueiredo, L Steier, L Canullo, G Steier, AP Roberts (2010) Evaluation of the antimicrobial effect of super-oxidised water (Sterilox) against Enterococcus faecalis in a bovine root canal model. Journal of Applied Oral Science. 18; 498-502.

    AS Jasni, P Mullany, H Hussain, AP Roberts. (2010) Demonstration of conjugative transposon (Tn5397) mediated horizontal gene transfer between Clostridium difficile and Enterococcus faecalis. Antimicrobial Agents and Chemotherapy.54; 4924-4926.

    S Hannan, D Ready, AS Jasni, M Rogers, J Pratten and AP Roberts. (2010) Transfer of antibiotic resistance by transformation with eDNA within oral biofilms. FEMS Immunology and Medical Microbiology.59. 345-349.

    MSM Brouwer, P Mullany, AP Roberts. (2010) Characterization of the conjugative transposon Tn6000 from Enterococcus casseliflavus 664.1H1 (formerly E. faecium 664.1H1). FEMS Microbiology Letters. 309; 71-76.

    LA Seville, AJ Patterson, KP Scott, P Mullany, D Ready, M Wilson, D Spratt, AP Roberts. (2009) Distribution of tetracycline and erythromycin resistance genes among the oral and faecal cultivable microbiota and metagenomic DNA. Microbial Drug Resistance. 15 (3), 159-166.

    X Bellanger, AP Roberts, C Morel, F Choulet, G Pavlovic, P Mullany, B Decaris, G Guédon (2009) Conjugative transfer of the integrative conjugative elements ICESt1 and ICESt3 from Streptococcus thermophilus. Journal of Bacteriology. 191 (8), 2764-2775.

    SK Henderson-Begg, AP Roberts, LMC Hall (2009). Diversity of putative Tn5253 like elements in Streptococcus pneumoniae. International Journal Antimicrobial Agents.33, 364-367.

    P Warburton, AP Roberts, E Allan, L Seville, H Lancaster, P Mullany (2009) Characterisation of tet(32) genes from oral metagenomes. Antimicrobial Agents and Chemotherapy 53 (1), 273-6.

    G Rossi-Fedele. AP Roberts (2007). A preliminary study investigating the survival of tetracycline resistant Enterococcus faecalis after root canal irrigation with high concentrations of tetracycline. International Endodontic Journal. 40 (10). 772-777.

    A Villedieu, AP Roberts, E Allan, H Hussain, R McNab D A Spratt, M Wilson and P Mullany. (2007). Determination of the genetic support for tet(W) in oral bacteria. Antimicrobial Agents and Chemotherapy. 51 (6). 2195-7.

    G Rossi-Fedele, W Scott, D Spratt, K Gulabivala, AP Roberts. (2006) Incidence and behaviour of Tn916-like elements within tetracycline resistant bacteria isolated from root canals. Oral Micro and Immunology.21. 218-222.

    D Ready, J Pratten, AP Roberts, R Bedi, P Mullany and M Wilson. (2006) The role of Veillonella spp. as a reservoir and donor of tetracycline resistance in the oral cavity. Antimicrobial Agents and Chemotherapy. 50 (8).2866-2868.

    M Sebaihia, BW Wren, P Mullany, NF Fairweather, N Minton, R Stabler, NR Thomson, AP Roberts, et al. (2006) The multidrug resistant human pathogen Clostridium difficile has a highly mobile, mosaic genome. Nature Genetics. 38 (7); 779-786.

    AP Roberts, IJ Davis, L Seville, A Villedieu, P Mullany. (2006) Characterisation of the ends and target site of a novel tetracycline resistance encoding conjugative transposon from Enterococcus faecium 664.1H1. Journal of Bacteriology.188 (12). 4356-4361.

    IJ Davis, AP Roberts, D Ready, H Richards, M Wilson, P Mullany. (2005). Linkage of a Novel Mercury Resistance Operon with Streptomycin Resistance on a Conjugative Plasmid in Enterococcus faecium. Plasmid. 54 (1). 26-38.

    HA Hussain, AP Roberts, P Mullany. (2005). Generation of an erythromycin sensitive derivative of Clostridium difficile strain 630 (630Δerm) and demonstration that the conjugative transposon Tn916ΔE enters the genome of this strain at multiple sites. Journal of Medical Microbiology. 54 (Pt 2), 137-41.

    H Lancaster, AP Roberts, R Bedi, M Wilson, P Mullany. (2004). Characterisation of Tn916S a Tn916-like Element Containing the Tetracycline Resistance Determinant tet(S). Journal of Bacteriology. 186 (13), 4395-4398.

    A Villedieu, ML Diaz-Torres, AP Roberts, N Hunt, R McNab, DA Spratt, M Wilson, P Mullany. (2004). Characterisation of the Genetic Basis for Erythromycin Resistance in Oral Bacteria. Antimicrobial Agents and Chemotherapy. 48 (6). 2298-2301.

    AP Roberts, C Hennequin, M Elmore, A Collignon, T Karjalainen, N Minton, P Mullany. (2003). Development of an integrative vector for the expression of antisense RNA in Clostridium difficile. Journal of Microbiological Methods. 55 (3). 617-24.

    D Ready, AP Roberts, J Pratten, D Spratt, M Wilson, P Mullany. (2002). Composition and antibiotic resistance profile of microcosm dental plaques before and after exposure to tetracycline. Journal of Antimicrobial Chemotherapy.49: 769-75

    AP Roberts, G Cheah, D Ready, J Pratten, M Wilson, P Mullany. (2001). Transfer of Tn916-like Elements in Microcosm Dental Plaques. Antimicrobial Agents and Chemotherapy. 45 (10). 2943-6

    AP Roberts, PA Johanesen, D Lyras, P Mullany, JI Rood. (2001) Comparison of Tn5397 from Clostridium difficile, Tn916 from Enterococcus faecalis and the CW459tet(M) element from Clostridium perfringens shows that they have similar conjugation regions but different insertion and excision modules. Microbiology. 147: 1243-1251.

    AP Roberts, V Braun. C von Eichel-Streiber, P Mullany. (2001) Demonstration that the Group II intron from the conjugative transposon Tn5397 splices in vivo but splicing is not a requirement for conjugal transfer. Journal of Bacteriology 183 (4). 1296-9.

    H Wang, AP Roberts, P Mullany. (2000). Characterisation of the target sites of Tn916 in Clostridium difficile and demonstration that a natural isolate contains a Tn916-like element inserted into the same site. FEMS Microbiology Letters 192: 15-20.

    H Wang, AP Roberts, D Lyras, JI Rood, M Wilks, P Mullany. (2000) Characterisation of the ends and target sequences of the novel conjugative transposon Tn5397 from Clostridium difficile: excision and circularization is mediated by the large resolvase, TndX. Journal of Bacteriology. 182 (13). 3775-3783.

    AP Roberts, J Pratten, M Wilson, P Mullany. (1999) Transfer of a conjugative transposon, Tn5397 in a model oral biofilm. FEMS Microbiology Letters 177: 63-6.