This research programme focuses on bacterial diseases of trees, both plantation and native tree species and to a lesser extent, fruit trees. We have two major research focuses – one on taxonomy and the other on pathogenicity factors exhibited by a select group of pathogens. The taxonomic research involves identifying new species using modern approaches, mainly in the Enterobacteriaceae. The majority of bacteria we have identified thus far have been opportunistic plant pathogens whilst others have been associated with plants as endophytes. This has led to a number of studies where we have attempted to understand how these opportunists can function as successful plant pathogens despite the fact that they occur in other ecological niches which are often diverse, such as in diesel fuel.

Our interest has primarily been on Pantoea ananatis and related Pantoea species, although we do have research projects on Xanthomonas spp. and Ralstonia solanacearum. P. ananatis is responsible for bacterial blight and die-back of Eucalyptus, brown stalk rot of maize and occurs on onion seed in South Africa. Our studies have centred on taxonomy and on developing rapid and reliable methods of distinguishing between the species of Pantoea. We are now expanding this research and are using a phylogenomic approach to examine this genus. Other elements currently under investigation include understanding the epidemiology and biology of primarily P. ananatis, but this has been expanded to include the other pathogens mentioned above as well. We have identified a number of pathogenicity factors in P. ananatis and this has given us some insight into its life as a phytopathogen. The approach we have used has involved both comparative and functional genomics. The pathogenicity factors investigated have included motility, Type VI secretion system, quorum sensing and exopolysaccharide production.

New Publications

Claassens R, Venter SN, Beukes CW, Stępkowski T, Chan WY, Steenkamp ET. (2023) Bradyrhizobium xenonodulans sp. nov. isolated from nodules of Australian Acacia species invasive to South Africa. Systematic and Applied Microbiology 10.1016/j.syapm.2023.126452
Theron E, Bophela KN, Bisschoff J, Shin G, Coutinho TA, Van der Waals JE. (2022) Survey of Soft Rot Pectobacteriaceae Infecting Potatoes in South Africa. Potato Research 10.1007/s11540-022-09598-1
Khanal M, Timilsina S, Bhatta BP, Bophela K, Coutinho T, Cochran K, Malla S. (2022) Pseudomonas uvaldensis sp. nov., a bacterial pathogen causing onion bulb rot. International Journal of Systematic and Evolutionary Microbiology 72(4) 10.1099/ijsem.0.005311
Avontuur JR, Palmer M, Beukes CW, Wai YC, Tasiya T, van Zyl E, Coetzee MPA, Stepkowski T, Venter SN, Steenkamp ET. (2022) Bradyrhizobium altum sp. nov., Bradyrhizobium oropedii sp. nov. and Bradyrhizobium acaciae sp. nov. from South Africa show locally restricted and pantropical nodA phylogeographic patterns. Molecular Phylogenetics and Evolution 167 10.1016/j.ympev.2021.107338 PDF
Van der Nest M, Hlongwane N, Hadebe K, Chan W, Van der Merwe N, De Vos L, Greyling B, Kooverjee B, Soma P, Dzomba E, Bradfield M, Muchadeyi F. (2021) Breed ancestry, divergence, admixture, and selection patterns of the Simbra crossbreed. Frontiers in Genetics 11:1796. 10.3389/fgene.2020.608650 PDF
Khumbuzile Bophela, Yolanda Petersen, Carolee Theresa Bull, Teresa Ann Coutinho. (2019) Identification of Pseudomonas isolates associated with bacterial canker of stone fruit trees in the Western Cape, South Africa. Plant Disease 10.1094/PDIS-05-19-1102-RE
Bophela KN, Venter SN, Wingfield MJ, Duran A, Tarigan M, Coutinho TA. (2019) Xanthomonas perforans: A tomato and pepper pathogen associated with bacterial blight and dieback of Eucalyptus pellita seedlings in Indonesia. . Australasian Plant Pathology 10.1007/s13313-019-00657-9 PDF
Beukes CW, Sereme TK, Phalane FL, Mthombeni LS, Palmer M, Hassen AI, Chan WY, Avontuur J, van Zyl E, Steenkamp ET, Venter SN. (2019) Paraburkholderia strydomiana sp. nov. and Paraburkholderia steynii sp. nov.: rhizobial symbionts of the fynbos legume Hypocalyptus sophoroides. Antonie van Leeuwenhoek 10.1007/s10482-019-01269-5
Avontuur JR, Palmer M, Beukes CW, Chan WY, Coetzee MPA, Blom J, Stępkowski T, Kyrpides NC, Woyke T, Shapiro N, Whitman WB, Venter SN, Steenkamp ET. (2019) Genome-informed Bradyrhizobium taxonomy: where to from here?. Systematic and Applied Microbiology 10.1016/j.syapm.2019.03.006
van der Nest MA, Wingfield MJ, McTaggart AR, Van Wyk S, De Vos L, Trollip C, Santana QC, Naidoo K, Dong TA, Wilken PM, Chan W-Y, Palmer M, Soal NA, Roodt D, Steenkamp ET, Wingfield BD. (2019) Genomic analysis of the aggressive tree pathogen Ceratocystis albifundus. Fungal Biology 10.1016/j.funbio.2019.02.002 PDF
Shin G, Schacterle JK, Shyntum DY, Moleleki LN, Coutinho T, Sundin GW. (2019) Functional characterization of a global virulence regulator Hfq and identification of Hfq-dependent sRNAs in the plant pathogen Pantoea ananatis. Frontiers in Microbiology 10:1-19. 10.3389/fmicb.2019.02075
Hammerbacher A, Coutinho TA, Gershenzon J. (2019) Roles of plant volatiles in defense against microbial pathogens and microbial exploitation of volatiles. Plant Cell and Environment 42:2827-2841.
Shutt VM, Shin G, van der Waals JE, Goszczynska T, Coutinho T. (2018) Characterization of Ralstonia strains infecting tomato plants in South Africa. Crop Protection 112:56-62. 10.1016/j.cropro.2018.05.013
Siphathele Sibanda, Stanford Kwenda, Collins K. Tanui, Divine Shyntum, Teresa Coutinho, Lucy Moleleki. (2018) Transcriptome profiling reveals the EanI/R quorum sensing regulon in Pantoea ananatis LMG 2665T. Genes 9(3):148. 10.3390/genes9030148
Palmer M, Steenkamp ET, Coetzee MPA, Avontuur JR, Chan WY, Van Zyl E, Blom J, Venter SN. (2018) Mixta gen. nov., a new genus in the Erwiniaceae. International Journal of Systematic and Evolutionary Microbiology 68:1396-1407. 10.1099/ijsem.0.002540
Otto M, Hammerbacher A, Petersen Y, Pierneef R, Coutinho TA. (2018) Phenolic compound degradation by Pseudomonas syringae phylogroup 2 strains. Journal of Plant Pathology 100(2):279-286.
Siphathele Sibanda, Lucy Moleleki, Divine Shyntum, Teresa Coutinho. 2018. Quorum Sensing in Gram-Negative Plant Pathogenic Bacteria. In: Advances in Plant Pathology. Intechopen., London SE1 9SG, United Kingdom, pp 67-89.
Otto M, Petersen Y, Roux J, Wright J, Courtinho. (2018) Bacterial canker of cherry trees, Prunus avium, in South Africa. European Journal of Plant Pathology 151:427-438. 10.1007/s10658-017-1384-5
De Maayer P, Aliyu H, Vikram S, Blom J, Duffy B, Cowan DA, Smits THM, Venter SN, Coutinho TA. (2017) Phylogenomic, pan-genomic, pathogenomic and evolutionary genomic insights into the agronomically relevant enterobacteria Pantoea ananatis and Pantoea stewartii. Frontiers in Microbiology 8(1755) 10.3389/fmicb.2017.01755
Beukes CW, Palmer M, Manyaka P, Chan W-Y, Avontuur JR, Van Zyl E, Huntemann M, Clum A, Pillay M, Palaniappan K, Varghese N, Mikhailova N, Stamatis D, Reddy TBK, Daum C, Shapiro N, Markowitz V, Ivanova N, Kyrpides N, Woyke T, Blom J, Whitman WB, Venter SN, Steenkamp ET. (2017) Genome data provides high support for generic boundaries in Burkholderia sensu lato. Frontiers in Microbiology 8(1154) 10.3389/fmicb.2017.01154 PDF
Venter SN, Palmer M, Beukes CW, Chan W-Y, Shin G, Van Zyl E, Seale T, Coutinho TA, Steenkamp ET. (2017) Practically delineating bacterial species with genealogical concordance. Antonie van Leeuwenhoek 110(10):1311-132. 10.1007/s10482-017-0869-8
Palmer M, Steenkamp ET, Coetzee MPA, Chan W-Y, Van Zyl E, De Maayer P, Coutinho TA, Blom J, Smits THM, Duffy B, Venter SN. (2017) Phylogenomic resolution of the bacterial genus Pantoea and its relationship with Erwinia and Tatumella. Antonie van Leeuwenhoek 110(10):1287-1309. 10.1007/s10482-017-0852-4
Weller-Stuart T, De Maayer P, Coutinho T. (2017) Pantoea ananatis: genomic insights into a versatile pathogen. Molecular Plant Pathology 18(9):1191-1198. 10.1111/mpp.12517
Weller-Stuart T, Toth I, De Maayer P, Coutinho T. (2017) Swimming and twitching motility are essential for attachment and virulence of Pantoea ananatis in onion seedlings. Molecular Plant Pathology 18(5):734-745. 10.1111/mpp.12432
Breedt G, Coutinho TA, Labuschagne N. (2017) Seed treatment with selected plant growth promoting rhizobacteria increases maize yield in the field. Annals of Applied Biology 171:229-236.
Moloto V, Goszczynska T, du Toit L, Coutinho TA. (2017) A new pathovar of Pseudomonas syringae, pathovar allii, isolated from onion plants exhibiting symptoms of blight. European Journal of Plant Pathology 147:591-603.
Zimudzi J, Coutinho TA, van der Waals J. (2017) Pathogenicity of fungi isolated from atypical skin blemishes on potatoes in South Africa and Zimbabwe. Potato Research 60:119-144.
Carstensen GD, Venter SN, Wingfield MJ, Coutinho TA. (2016) Two Ralstonia species associated with bacterial wilt of Eucalyptus. Plant Pathology 66:393-403. 10.1111/ppa.12577 PDF
Sibanda S, Theron J, Shyntum DY, Moleleki LN, Coutinho TA. (2016) Characterization of two LuxI/R homologs in Pantoea ananatis LMG 2665 T. Canadian Journal of Microbiology 62(11):893-903. 10.1139/cjm-2016-0143
Palmer M, De Maayer P, Poulsen M, Steenkamp ET, Van Zyl E, Coutinho TA, Venter SN. (2016) Draft genome sequences of Pantoea agglomerans and Pantoea vagans isolates associated with termites. Standards in Genomic Sciences 11(23) 10.1186/s40793-016-0144-z PDF
Kwenda S, Gorshkov V, Ramesh AM, Naidoo S, Rubagotti E, Birch PRJ, Moleleki LN. (2016) Discovery and profiling of small RNAs responsive to stress conditions in the plant pathogen Pectobacterium atrosepticum. BMC Genomics 17(1) 10.1186/s12864-016-2376-0
du Raan S, Coutinho TA, van der Waals JE. (2015) Cardinal temperature differences, determined in vitro, between closely related species and subspecies of pectinolytic bacteria responsible for blackleg and soft rot on potatoes. European Journal of Plant Pathology 144(2):361-369. 10.1007/s10658-015-0773-x
Steenkamp ET, van Zyl E, Beukes CW, Avontuur J, Chan W-Y, Palmer M, Mthombeni LS, Phalane FL, Sereme TK, Venter SN. (2015) Burkholderia kirstenboschensis sp. nov. nodulates papilionoid legumes indigenous to South Africa. Systematic and Applied Microbiology 38(8):545-554. 10.1016/j.syapm.2015.09.003
De Maayer P, Chan W-Y, Martin DAJ , Blom J, Venter SN, Duffy B, Cowan DA, Smits THM, Coutinho TA. (2015) Integrative conjugative elements of the ICEPan family play a potential role in Pantoea ananatis ecological diversification and antibiosis. Frontiers in Microbiology 6:576. 10.3389/fmicb.2015.00576
Nesamari R, Millar IM, Coutinho TA, Roux J. (2015) South African cycads at risk: Aulacaspis yasumatsui (Hemiptera: Coccoidea: Diaspididae) in South Africa. African Entomology 23(1):198-206.
Shyntum D, Theron J, Moleleki L, Toth I, Venter SN, Coutinho TA. (2015) Pantoea ananatis utilizes a type VI secretion system for pathogenesis and bacterial competition. Molecular Plant-Microbe Interactions 28(4):420-431. 10.1094/MPMI-07-14-0219-R
Coutinho TA, van der Westhuizen L, Roux J, McFarlane SA, Venter SN. (2015) Significant host jump of Xanthomonas vasicola from sugarcane to a Eucalyptus grandis clone in South Africa. Plant Pathology 64(3):576-581. 10.1111/ppa.12298
Weller-Stuart T, Chan W-Y, Coutinho TA, Venter SN, Smits THM, Duffy B, Goszczynska T, Cowan DA, de Maayer P. (2014) Draft genome sequences of the onion center rot pathogen Pantoea ananatis PA4 and maize brown stalk rot pathogen P. ananatis BD442. Genome Announcements 2(4) e00750-14
De Maayer P, Chan WY, Rubagotti E, Venter SN, Toth IK, Birch PR, Coutinho TA. (2014) Analysis of the Pantoea ananatis pan-genome reveals factors underlying its ability to colonize and interact with plant, insect and vertebrate hosts. BMC Genomics 15:404. 10.1186/1471-2164-15-404 PDF
Ngadze E, Coutinho TA, Icishahayo D, van der Waals JE. (2014) Effect of calcium soil amendments on phenolic compounds and soft rot resistance in potato tubers. Crop Protection 62:40-45. 10.1016/j.cropro.2014.04.009
Mitchell RG, Wingfield MJ, Steenkamp ET, Roux J, Verryn S, Coutinho TA. (2014) Comparison of the tolerance of Pinus patula seedlings and established trees to infection by Fusarium circinatum. Southern Forests 76(3):151-159. 10.2989/20702620.2014.899061 PDF
Shyntum DY, Venter SN, Moleleki LN, Toth I, Coutinho TA. (2014) Comparative genomics of type VI secretion systems in strains of Pantoea ananatis from different environments. BMC Genomics 15:163. 10.1186/1471-2164-15-163
Steenkamp ET, Makhari OM, Coutinho TA, Wingfield BD, Wingfield MJ. (2014) Evidence for a new introduction of the pitch canker fungus Fusarium circinatum in South Africa. Plant Pathology 63(3):530-538. 10.1111/ppa.12136 PDF
Bull CT, Coutinho TA, Denny TP, Firrao G, Fischer-Le Saux M, Li X, Saddler GS, Scortichini M, Stead DE, Takikawa Y. (2014) List of new names of plant pathogenic bacteria (2011-2012). Journal of Plant Pathology 96(2):223-226. 10.4454/JPP.V96I2.026 PDF
Reva ON, Chan WY, Benzuidt OKI, Lapa SV, Safronova LA, Avdeeva LV, Borriss R. 2014. Genetic barcoding of bacteria and its microbiological and biotechnological applications. In: Bioinformatics and Data Analysis in Microbiology. Bishop OT. (eds). Caister Academic Press, Norfolk, pp 231-245.
Roux J, Greyling I, Coutinho TA, Verleur M, Wingfield MJ. (2013) The Myrtle rust pathogen, Puccinia psidii, discovered in Africa. IMA Fungus 4:155-159. 10.5598/imafungus.2013.04.01.14 PDF
Chan WY, Dietel K, Lapa SV, Avdeeva LV, Borriss R, Reva ON. (2013) Draft genome sequence of Bacillus atrophaeus UCMB-5137, a plant-growth-promoting rhizobacterium. Genome Announcements 1(3):1-2. 10.1128/genomeA.00233-13 PDF
Kubheka GC, Coutinho T, Moleleki N, Moleleki LN. (2013) Colonisation patterns of a mCherry-tagged Pectobacterium carotovorum subsp. brasiliense in potato. Phytopathology 103(12):1269-1279. 10.1094/PHYTO-02-13-0049-R
Le Roux WJ, Chan WY, De Maayer P, De Maayer P, Venter SN. (2013) Genome Sequence of Vibrio cholerae G4222, a South African Clinical Isolate. Genome Announcements 1(2):1-2. 10.1128/genomeA.00040-13 PDF
Mitchell RG, Wingfield MJ, Hodge GR, Dvorak WS, Coutinho TA. (2013) Susceptibility of provenances and families of Pinus maximinoi and Pinus tecunumanii to frost in South Africa. New Forests 44:135-146. 10.1007/s11056-012-9306-z PDF