1 Introduction

In 2020, a new classification of the genus previously known as Lactobacillus was proposed based on biochemical, phylogenetic, and taxonomic differences between the groups/species forming this genus. A team of scientists proposed a definition of 25 new genera (Zheng et al., 2020). As of March 2020, the Lactobacillus genus was hosting 261 different species. This group of species was extremely diverse regarding their genotypic, phenotypic, and ecological characteristics, and this was one of the driving arguments for proposing 25 new genera. Modern taxonomy is based on phylogenetic approaches, and developments in biomolecular sciences justified the creation of the proposed new taxonomical organisation for these lactic acid bacteria (Zheng et al., 2020).

However, with the introduction of the 25 new genera, new problems emerged, one of which was linked to consistent abbreviations for each genus name. When publishing scientific papers, according to the rules of the journals (publishers, societies, etc.), after being introduced, the genus name is supposed to be abbreviated. In the past, the rules were simple and clear. For example, before changes and the introduction of new genus names, Lactobacillus was normally abbreviated as ‘L.’ or ‘Lb.’ Abbreviations such as ‘Le.’, ‘Lu.’ or ‘Leu.’ are already used for Leuconostoc; ‘Lc.’ or ‘Lac.’ for Lactococcus, ‘L.’ or ‘Lis.’ for Listeria, not to forget the existence of several other genera abbreviated as ‘L.’. With a diversity of new names derived from the old Lactobacillus genus designation, and to prevent confusion, the introduction of new abbreviations seems inevitable.

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Recommendations for standardised abbreviations for the former Lactobacillus genera, reclassified in the year 2020

Citation: Beneficial Microbes 15, 1 (2024) ; 10.1163/18762891-20230114

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(Continued.)

Citation: Beneficial Microbes 15, 1 (2024) ; 10.1163/18762891-20230114

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2 Proposal

In the proposed abbreviations (Table 1), the first two letters of new genus names were taken into consideration in addition to ‘b’, associated with the word ‘bacillus’, part of the word ‘lactobacillus’, referring to the morphology of the discussed bacterial species. In case the second letter has been already in use for an alphabetically earlier name, an additional letter was selected. In addition, two-letter abbreviations are suggested by similar arguments.

The use of one-letter abbreviations cannot be regarded as an option since this will generate confusion among already existing genera and even new proposed names. Moreover, we need to admit that some species names have been used in combination with different genus names, such as cases of Lactobacillus lactis, Lactococcus lactis, Leuconostoc lactis, and abbreviations as simple L. lactis can be misleading regarding the correct genus name of 3 different species. In case there are no other microbial species in the specific publication (scientific paper, popular material, or other printed material) causing a conflict in abbreviation in the same single letter, representing the first letter of the genus name, a one-letter code abbreviation can be used for practical reasons.

An additional problem that needs to be solved is citing papers from before April 2020. In this case, it may be appropriate to refer to the former genus Lactobacillus, whenever possible, as ‘lactobacilli’ to avoid its confusion with a new genus Lactobacillus according to the classification suggested by Zheng et al. (2020). If appropriate, when referring to manuscripts published prior to 2020 the former genus name could be mentioned as well, for instance, ‘Lacticaseibacillus (formerly Lactobacillus) rhamnosus’.

We believe this proposal will be helpful in the preparation of scientific manuscripts in a standardised manner across the scientific community. According to accepted rules, the first mentioning of a species name should be in full and followed by the appropriate abbreviation. Misunderstanding and misleading interpretations. could be avoided by following harmonised abbreviations.

Moreover, it would serve the purpose of harmonisation if websites such as http://lactotax.embl.de/wuyts/lactolax, http://lactobacillus.uantwerpen.be and other internet-based information tools could provide supporting information for the link between previous and new genus names, as affected by the changes in the nomenclature of the (non-restrictive) genus Lactobacillus (Zhang et al., 2020).

Authors’ contribution

Concept: SDT, ALBP; writing of the manuscript: SDT; Intellectual support, corrections and editing: SDT, ALBP, KV, WHH, MLC.

Conflict of interest

The authors have declared no conflict of interest.

Funding

SDT was partially supported by FAPESP (Grant 2013/07914-8), University of Sao Paulo, Sao Paulo, SP, Brazil and Centre for Research and Development in Agrifood Systems and Sustainability, funded by FCT (UIDB/05937/2020 and UIDP/05937/2020), Fundação para a Ciência e a Tecnologia, Portugal; MLC was partially supported by the Ministry of Science and Higher Education of the Russian Federation (Project Number 075-15-2019-1880).