Correct interpretation of actinomycete imagery using scanning electron microscopy
D. İpek Kurtböke A *A Centre for Bioinnovation, School of Science, Technology and Engineering, University of the Sunshine Coast, Maroochydore DC, Qld 4558, Australia.
Dr Kurtböke is currently a senior lecturer at the University of the Sunshine Coast (USC) in Australia and one of the members of the Genecology Research Centre of the USC, conducting research in applied, industrial and environmental microbiology. She is an internationally reputed actinomycetologist and she has been in the field of biodiscovery since 1982 conducting research into discovery of novel and potent therapeutic compounds produced by actinomycetes in Turkey, Italy, the UK, and Australia with leading pharmaceutical companies. She has been an Executive Board member of the World Federation of Culture Collections (WFCC) since 2000, currently serving her second term as the President of the Federation. She is also one of the members of the International Committee on Taxonomy of Viruses (ICTV)’s, Bacterial Viruses Subcommittee. She has editorial duties in different journals including Marine Drugs, Diversity and Frontiers Marine Science/Marine Biotechnology. |
Microbiology Australia 43(1) 28-31 https://doi.org/10.1071/MA22009
Submitted: 17 January 2022 Accepted: 1 March 2022 Published: 22 April 2022
© 2022 The Author(s) (or their employer(s)). Published by CSIRO Publishing on behalf of the ASM. This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND)
Abstract
Antibiotic discovery was one of the most significant advances in therapeutic medicine following the advances in fermentation technology owing to Howard Florey and his associates. The ‘Golden era’ of antibiotics following the first discoveries in the laboratory of Waksman and his colleagues from a group of microorganisms known as actinomycetes lasted for 34 years (1940–1974). These fascinating microorganisms especially the members of the genus Streptomyces gave us the majority of the known antibiotics we use today, like streptomycin, kanamycin, neomycin, gentamicin, vancomycin and many more. To be able to produce these antibiotics in large-scale, the producer actinomycetes had to be selectively isolated. This resulted in a collaboration of over 40 laboratories from 18 different countries called ‘The International Streptomyces Project (ISP)’. The isolates generated in this project were studied in-depth including their morphologies together with their bioactivity. One of the components of these investigation was the correct interpretation of actinomycete morphology including the use of scanning electron microscopy. At the end of the first European Actinomycete Conference in Bradford University in England (1984), I had the opportunity to be trained by late Professor Cross on actinomycete growth morphologies. Thirty-eight years later when I witness the frequent difficulties students encounter in the interpretation of the actinomycete SEM images, I decided to write this paper and pass the skills given to me by late Professor Cross to the younger generation.
Keywords: Actinomycetales, Actinomycetes, Actinomycetia, Actinomycetota, growth morphology, SEM imagery, Streptomyces, taxonomy.
References
[1] Harz, CO et al.. (1879) Actinomyces bovis ein neuer Schimmel in dem Geweben des rindes. Jahrebericht der K Central-Thieraznei Schule in Müchen für 1877–1879 5, 125–140.[2] Buchanan, RE et al.. (1917) Studies in the nomenclature and classification of the bacteria II. The primary subdivisions of the schizomycetes. J Bacteriol 2, 155–164.
| Studies in the nomenclature and classification of the bacteria II. The primary subdivisions of the schizomycetes.Crossref | GoogleScholarGoogle Scholar | 16558735PubMed |
[3] Buchanan, RE et al.. (1918) Studies in the classification and nomenclature of the bacteria VIII. The subgroups and genera of the Actinomycetales. J Bacteriol 3, 403–406.
| Studies in the classification and nomenclature of the bacteria VIII. The subgroups and genera of the Actinomycetales.Crossref | GoogleScholarGoogle Scholar | 16558803PubMed |
[4] Stackebrandt, E et al.. (1997) Proposal for a new hierarchic classification system, Actinobacteria classis nov. Int J Syst Evol Microbiol 47, 479–491.
| Proposal for a new hierarchic classification system, Actinobacteria classis nov.Crossref | GoogleScholarGoogle Scholar |
[5] Goodfellow M (2012) Phylum XXVI. Actinobacteria phyl. nov. In Bergey’s Manual of Systematic Bacteriology, Second Edition, Volume 5, The Actinobacteria, Part A. (Goodfellow M, et al., eds). pp. 33–34. Springer, New York, NY.
[6] Nouioui, I et al.. (2018) Genome-based taxonomic classification of the phylum Actinobacteria. Front Microbiol 9, 2007.
| Genome-based taxonomic classification of the phylum Actinobacteria.Crossref | GoogleScholarGoogle Scholar | 30186281PubMed |
[7] Salam, N et al.. (2020) Update on the classification of higher ranks in the phylum Actinobacteria. Int J Syst Evol Microbiol 70, 1331–1355.
| Update on the classification of higher ranks in the phylum Actinobacteria.Crossref | GoogleScholarGoogle Scholar | 31808738PubMed |
[8] Williams ST et al. (eds) (1989) Bergey’s Manual of Systematic Bacteriology, vol. 4. Williams and Wilkins, Baltimore.
[9] Oren, A and Garrity, GM (2021) Valid publication of the names of forty-two phyla of prokaryotes. Int J Syst Evol Microbiol 71, 005056.
| Valid publication of the names of forty-two phyla of prokaryotes.Crossref | GoogleScholarGoogle Scholar |
[10] Waksman, SA and Henrici, AT (1943) The nomenclature and classification of the actinomycetes. J Bacteriol 46, 337–341.
| The nomenclature and classification of the actinomycetes.Crossref | GoogleScholarGoogle Scholar | 16560709PubMed |
[11] Park, YH et al.. (1993) Suprageneric classification of Thermoactinomyces vulgaris by nucleotide sequencing of 5S ribosomal. RNA Zentralblatt für Bakteriologie 278, 469–478.
| Suprageneric classification of Thermoactinomyces vulgaris by nucleotide sequencing of 5S ribosomal.Crossref | GoogleScholarGoogle Scholar | 7688999PubMed |
[12] Williams ST, Wellington EMH (1982) Actinomycetes. In Methods of Soil Analysis, Part 2. Chemical, Microbiological Properties, 2nd edn (Page AL et al., eds). pp. 969–987.
[13] Goodfellow M, Cross T (1984) Classification. In The Biology of the Actinomycetes (Goodfellow M, et al., eds). pp. 7–164. Academic Press, London.
[14] Locci R (1989) Streptomycetes and related genera, Section 29. In Bergey’s Manual of Systematic Bacteriology, vol. 4, (Williams ST et al., eds). pp. 2451–2492. Williams and Wilkins, Baltimore.
[15] Cross T (1989) Growth and examination of actinomycetes-some guidelines. In Bergey’s Manual of Systematic Bacteriology, vol. 4 (Williams ST et al., eds). pp. 2340–2343. Williams and Wilkins, Baltimore.
[16] Nonomura, H et al.. (1974) Key for classification and identification of 458 species of the streptomycetes included in the ISP. J Ferment Technol 52, 78–92.
[17] English, AL et al.. (2017) Evaluation of fermentation conditions triggering increased antibacterial activity from a near-shore marine intertidal environment-associated Streptomyces species. Synth Syst Biotechnol 2, 28–38.
| Evaluation of fermentation conditions triggering increased antibacterial activity from a near-shore marine intertidal environment-associated Streptomyces species.Crossref | GoogleScholarGoogle Scholar | 29062959PubMed |
[18] Kurtböke DI (2017) Bioactive actinomycetes: reaching rarity through sound understanding of selective culture and molecular diversity. In Microbial Resources: From Functional Existence in Nature to Applications (Kurtböke DI, ed.). pp. 45–76. Academic Press.
[19] Barka, EA et al.. (2016) Taxonomy, physiology, and natural products of Actinobacteria. Microbiol Mol Biol Rev 80, 1–43.
| Taxonomy, physiology, and natural products of Actinobacteria.Crossref | GoogleScholarGoogle Scholar | 26609051PubMed |
[20] Williams, ST et al.. (1970) Further investigations of actinomycetes by scanning electron microscopy. Microbiology 62, 67–73.
| Further investigations of actinomycetes by scanning electron microscopy.Crossref | GoogleScholarGoogle Scholar |
[21] Williams, ST and Davies, FL (1967) Use of a scanning electron microscope for the examination of actinomycetes. Microbiology 48, 171–177.
| Use of a scanning electron microscope for the examination of actinomycetes.Crossref | GoogleScholarGoogle Scholar |
[22] Prakash, D and Nawani, NN (2014) A rapid and improved technique for scanning electron microscopy of actinomycetes. J Microbiol Methods 99, 54–57.
| A rapid and improved technique for scanning electron microscopy of actinomycetes.Crossref | GoogleScholarGoogle Scholar | 24556287PubMed |
[23] Kurtböke DI (ed.) (2022) Importance of Microbiology Teaching and Microbial Resource Management for Sustainable Futures. Academic Press.
[24] Kurtböke, I et al.. (2012) From Actinomycin onwards: Actinomycete success stories. Microbiol Aust 33, 108–110.
| From Actinomycin onwards: Actinomycete success stories.Crossref | GoogleScholarGoogle Scholar |
