International Journal of Systematic and Evolutionary (2009), 59, 2122–2128 DOI 10.1099/ijs.0.003566-0

Emended descriptions of the genera and Corallococcus, typification of the species Myxococcus stipitatus and Myxococcus macrosporus and a proposal that they be represented by neotype strains. Request for an Opinion

Elke Lang and Erko Stackebrandt

Correspondence DSMZ – Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH, Inhoffenstr. Elke Lang 7B, 38124 Braunschweig Germany [email protected]

The genus Corallococcus was separated from the genus Myxococcus mainly on the basis of differences in morphology and consistency of swarms and fruiting bodies of the respective members. Phylogenetic, chemotaxonomic and physiological evidence is presented here that underpins the separate status of these phylogenetically neighbouring genera. Emended descriptions of the two genera are presented. The data also suggest that the species Corallococcus macrosporus belongs to the genus Myxococcus. To the best of our knowledge, the type strains of the species Myxococcus macrosporus and Myxococcus stipitatus are not available from any established culture collection or any other source. A Request for an Opinion is made regarding the proposal that strain Cc m8 (5DSM 14697 5CIP 109128) be formally recognized as the neotype strain for the species Myxococcus macrosporus, replacing the designated type strain Windsor M271T, and that strain Mx s8 (5DSM 14675 5JCM 12634) be formally recognized as the neotype strain for the species Myxococcus stipitatus, replacing the designated type strain Windsor M78T.

Introduction The genus Myxococcus was described by Thaxter (1892), Within the family , delineation of genera, who first recognized that the , formerly descriptions of species and affiliations of strains to species assigned to the fungi, were in fact . The species are based primarily on the morphology of vegetative cells, names Myxococcus disciformis, M. flavescens, M. fulvus, M. swarming colonies, fruiting bodies and myxospores. The stipitatus, M. xanthus, M. virescens, M. macrosporus and M. genus Corallococcus was established for strains that build coralloides have since been validly published. M. disciformis fruiting bodies with finger-like projections or of even more was later reclassified as Angiococcus disciformis (Hook et al., bizarre, coralloid shape with cartilaginous consistency. In 1980). In 1981, Reichenbach and Dworkin proposed the contrast, fruiting bodies of Myxococcus species are larger genus name Corallococcus for the former genus and globular, form knobs, either constricted at the base or ‘Chondrococcus’, but the genus name had no standing in on a stalk, and are of a soft consistency (Reichenbach & nomenclature until recently. In his description of the genus Dworkin, 1981). Other properties cited by Reichenbach Corallococcus, Reichenbach (2005c) included the taxa (2005a) as being useful for the differentiation of the two M. coralloides,‘Myxococcus exiguus’ and ‘Chondrococcus genera are that Myxococcus strains are generally sensitive to macrosporus’asCorallococcus coralloides comb. nov., kanamycin, whereas about 60 % of Myxococcus isolates Corallococcus exiguus nom. rev., comb. nov. and grow in the presence of streptomycin, that Corallococcus Corallococcus macrosporus comb. nov., respectively. The strains show opposite reactions towards these antibiotics, genus name was accepted as being validly published, but that Corallococcus strains produce squalene while the species name Corallococcus macrosporus was not Myxococcus strains do not and that Myxococcus strains accepted as being synonymous with Myxococcus macro- are more tolerant of NaCl (up to 2 %). sporus on formal grounds (Reichenbach, 2007; see details below).

Profiles of phenotypic characters and fatty acids of individual strains are A small number of taxonomic studies have recently been available with the online version of this paper. published that elucidate the phylogenetic status of the

2122 003566 G 2009 IUMS Printed in Great Britain Request for an Opinion genera Myxococcus and Corallococcus. In a broad 16S rRNA M. stipitatus, for which culturable type strains are not gene sequence-based analysis of almost all myxobacterial available from any established culture collection or any genera described at that time, Spro¨er et al. (1999) found other source. members of the genus Corallococcus (genus name not validly published at the time) branching close but adjacent Differentiation of the genus Corallococcus from to members of the genus Myxococcus. M. macrosporus the genus Myxococcus strains Cc m7 and Cc m8 (5DSM 14697) did not cluster with other members of the genus Corallococcus but within Genomic properties and the composition of whole-cell the radiation of Myxococcus strains. As the 16S rRNA gene fatty acids and physiological properties of several strains of sequence similarities among myxococcal strains were the genus Corallococcus were described previously (Spro¨er higher than 98.2 % and only slightly lower between et al., 1999; Stackebrandt & Pa¨uker, 2005; Stackebrandt myxococci and members of the genus Corallococcus (97– et al., 2007). In this study, these investigations were 98 %), no decision on the taxonomic status of Myxococcus expanded to representatives of different Myxococcus macrosporus was made. species. Published 16S rRNA gene sequences were aligned In a more extensive study on the intrageneric structure of by the ae2 editor (Maidak et al., 1997) and by ARB (Ludwig the genus Corallococcus (Stackebrandt & Pa¨uker, 2005; et al., 2004) and dendrograms were generated using Stackebrandt et al., 2007), 37 strains of Corallococcus, neighbour-joining (Saitou & Nei, 1987) and least-squares Corallococcus macrosporus DSM 14697T and M. xanthus algorithms (De Soete, 1983) as well as maximum- DSM 16526T were analysed with respect to 16S rRNA, gyrB, likelihood analysis (Olsen et al., 1994). Bootstrap analysis rpoB, fusA and lepA gene sequence similarities. In each of was used to evaluate the significance of the tree topology the dendrograms calculated from these genes, Corallococcus statistically by performing 1000 resamplings (Felsenstein, macrosporus DSM 14697T clustered adjacent to M. xanthus 1993). The topologies of all dendrograms thus generated DSM 16526T but significantly outside the cluster defined were very similar (Fig. 1; least-squares analysis) in that by Corallococcus coralloides DSM 2259T and Corallococcus Corallococcus strains and Myxococcus strains formed two exiguus DSM 14696T. This finding was corroborated by well-separated clades supported by bootstrap values of significant differences in fatty acid profiles, Riboprint 99 %. The exception was Corallococcus macrosporus DSM T patterns and metabolic reactions (Stackebrandt et al., 14697 , which clustered within the Myxococcus clade in all 2007). It thus appeared that the morphology-based formal the dendrograms generated, adjacent to the three highly decision to classify M. macrosporus as a member of the related species M. virescens, M. flavescens and M. xanthus. genus Corallococcus is not supported by the chemotaxo- Strains from the DSMZ were used as reference strains for nomic, genetic and metabolic properties analysed. physiological tests and fatty acid analysis (Table 1). The Results of these studies raised afresh the question of cultures were maintained on bakers’ yeast agar (VY/2; DSM whether the separate status of the genera Corallococcus and medium 9). Test media were inoculated with cells 2 Myxococcus is justified and how and where to delineate the suspended in medium MD1 (l 1: 3 g casitone, 0.7 g genus boundaries. The aims of this study were threefold. CaCl2 .2H2O, 2 g MgSO4 .7H2O) after growth on CY agar 21 First, to amend the physiological and chemotaxonomic (l : 3 g casitone, 1 g CaCl2 .2H2O, 1 g yeast extract, 15 g description of Myxococcus species in order to accumulate agar; pH 7.2) for 2 days. Incubations were carried out at evidence as to whether or not the separate status of the two 28 uC. Starch and xylan hydrolysis were tested on overlay genera Myxococcus and Corallococcus is justified, second, to agar. The first layer consisted of water agar (l21:1g support the taxonomic position of Corallococcus macro- CaCl2 .2H2O and 15 g agar agar), the second of starch or sporus as a member of the genus Myxococcus, and third, to xylan agar (l21: 2 g native potato starch or 5 g oat spelt propose neotype strains for the species M. macrosporus and xylan, 0.5 g casitone, 1 g CaCl2 .2H2O, 1 g MgSO4 .7H2O,

Fig. 1. Least-squares phylogenetic tree of Myxococcus and Corallococcus strains, based on 16S rRNA gene sequences. Bootstrap values are percentages calculated from 1000 resamplings. Bar, 2 % nucleotide substitutions. http://ijs.sgmjournals.org 2123 E. Lang and E. Stackebrandt

Table 1. Myxococcus strains investigated

All strains except DSM 16525T, DSM 16526T, DSM 6796, DSM 2260T and DSM 4946T were isolated by H. Reichenbach. The origins and sequence accession numbers of the Corallococcus strains included are listed in Stackebrandt & Pa¨uker (2005).

Strain Other strain designation(s) Isolation source Geographical origin

Myxococcus fulvus DSM 16525T M17T 5ATCC 25199T Soil Canada DSM 51991 Mx f53 Rabbit faeces Spain, Punta del Hidalgo DSM 16526T FBT 5ATCC 25232T 5NCIMB 9412T 5NBRC Soil Unknown 13542T 5CCUG 2079T 5CIP 107069T T DSM 6796 FBt/T 5Mx x6 Derivative of strain FB DSM 435 Mx x1 Soil with roots Liberia DSM 52389 Mx x29 Hare faeces Germany, Siebengebirge DSM 52395 Mx x36 Goat faeces India, near Madras Myxococcus virescens DSM 2260T M22T 5ATCC 25203T 5NCIMB 13350T Soil Canada 5NBRC 100334T DSM 52256 Mx v71 Goat faeces Turkey, near Alanya Myxococcus flavescens DSM 4946T ATCC 51243T 5IAM 13189T 5JCM 6245T Coastal soil Japan, Kanagawa DSM 52472 Mx fl1 Soil Japan, near Kanagawa coast Myxococcus stipitatus DSM 14675 Mx s8 Lateric soil Brazil, Iguaca DSM 14676 Mx s1 Rotting wood and soil Thailand, Bangkok Myxococcus (Corallococcus) macrosporus DSM 14697T*Ccm8T Soil with decaying plant South Africa material DSM 14690 Cc m15 Bear faeces Canada, Ontario

*Type strain of Corallococcus macrosporus; proposed here as neotype strain of Myxococcus macrosporus.

10 g agar). The plates were evaluated after covering with Aesculin hydrolysis, detected as darkening of the medium, Lugol’s solution after 5 days (starch) and 4 days (xylan) of was positive (though weak for some strains) for strains of incubation. Clear haloes with a diameter larger than that of Corallococcus coralloides and Corallococcus exiguus and the swarms and staying for longer than 5 min were scored negative for strains of the genus Myxococcus and of as positive. Salt tolerance was measured as growth on CY Corallococcus macrosporus. Three features mentioned by agar plates containing 15 g NaCl l21, incubated for up to Reichenbach (2005) as being useful to distinguish members 3 weeks. Aesculin hydrolysis was tested on slants with the of the genera Corallococcus and Myxococcus were composition (l21) 3 g casitone, 1 g yeast extract, 1 g re-evaluated. Most of the Myxococcus strains and the aesculin, 1 g sodium citrate and 0.05 g ground ferric strains of Corallococcus macrosporus showed growth on citrate. Slants were read after 8 days. Tolerance against agar plates containing 1.5 % NaCl, while the authentic antibiotics was determined on VY/2 agar plates containing Corallococcus strains did not. Four of nine selected 250 mg kanamycin sulphate or 50 mg streptomycin Corallococcus strains were resistant to kanamycin. sulphate l21. Growth was observed for up to 5 days. Resistance to streptomycin was displayed by strains of the species M. virescens, M. flavus, M. fulvus and M. The results of the physiological tests are summarized in stipitatus, while three out of four strains of M. xanthus were Table 2; a compilation of results of every strain studied is susceptible to this antibiotic. The Corallococcus strains did supplied as Supplementary Table S1 in IJSEM Online. The not grow in the presence of streptomycin, except strains of Corallococcus coralloides and Corallococcus exiguus Corallococcus macrosporus, which again showed the same hydrolysed starch and xylan so strongly that colourless reactions as the Myxococcus strains (Table 2). haloes that exceeded the size of the swarms appeared after covering of the agar plates with Lugol’s solution. In In order to substantiate the discrimination between the two contrast, the strains of the genus Myxococcus, including genera, commercially available test strips for bacterial Corallococcus macrosporus, only showed very weak, light- identification were tested. Neither API 20NE (bioMe´rieux) blue haloes that never exceeded the size of the swarms. nor Biolog GN microplates (testing for the metabolism of

2124 International Journal of Systematic and Evolutionary Microbiology 59 Request for an Opinion

Table 2. Features that differentiate the genera Myxococcus and Corallococcus

Myxococcus (Corallococcus) macrosporus includes strain Cc m8. Results for individual strains are given in Supplementary Tables S1 and S2. V, Variable results (numbers of positive strains given in parentheses); for reactions to antibiotics, positive indicates resistance, growth, and negative indicates sensitivity, no growth; ND, not detected.

Feature Myxococcus Corallococcus Myxococcus (Corallococcus) macrosporus

Number of strains 11 13 2 Starch decomposition 2 + 2 Xylan decomposition 2 + 2 Aesculin decomposition 2 + 2 + Growth at 1.5 % NaCl V (8) 2 Resistance to: 21 Kanamycin sulphate (250 mg l ) 2 V (4) 2 21 + Streptomycin sulphate (50 mg l ) V (9) 2 Fatty acid content (% of total)

iso-C13 : 0 0.6–1.6 2.7–5.1 0.5–0.6 iso-C14 : 0 ND 0.3–2.1 ND anteiso-C17 : 1 2.6–7.4 12.1–26.5 1.9–3.2 C16 : 1v5c 9.9–20.6 1.123.2 18.1–22.3 C16 : 1v11c 0.2–1.4 ND 1.2–1.3

95 substrates) could be adapted in such a way that 9.9 % in Myxococcus strains, while the proportion was meaningful reproducible results were obtained with 3.2 % or less in Corallococcus strains; iso-C13 : 0 and anteiso- myxobacteria. In contrast, test strips that predominantly C17 : 1 were present in proportions of at least 2.7 and determine reactions, namely API Campy and API 12.0 %, respectively, in Corallococcus strains, but signifi- ZYM (bioMe´rieux), resulted in patterns for Corallococcus cantly less in Myxococcus strains; C16 : 1v11c was present in strains that could be evaluated (Stackebrandt et al., 2007). Myxococcus strains but not in the Corallococcus strains However, the features offered by these strips were not (Table 2). The strains of Corallococcus macrosporus helpful in distinguishing members of the genera displayed profiles similar to the profiles of members of Myxococcus and Corallococcus,asMyxococcus strains the genus Myxococcus. displayed the same reactions as described for Corallococcus (results not shown). Only the reduction of The bifurcation in the phylogenetic tree matches the triphenyltetrazolium chloride tended to be positive for differences in fatty acid profiles and grouped species of the Corallococcus and negative for Myxococcus strains. genus Myxococcus and Corallococcus macrosporus in one cluster and the remaining Corallococcus strains in another. Since this Biomass for whole-cell fatty acid analysis was cultivated on demarcation is in good agreement with the physiological CY agar for 2 days at 28 uC, after inoculation with a properties (based upon different reactions towards starch, suspension of cells grown on VY/2 agar. Fatty acid methyl xylan and aesculin, tolerance of NaCl, streptomycin and esters were obtained as described previously (Ka¨mpfer & kanamycin), we found evidence to support the separate status Kroppenstedt, 1996) and separated by a gas chromato- of the two genera Myxococcus and Corallococcus,asindicated graph (model 5898A; Hewlett Packard). Peaks were in the emended descriptions below. automatically computed using the Microbial Identifi- cation standard software package (Sasser, 1990). Emended description of the genus Myxococcus The whole-cell fatty acid patterns of the Corallococcus Thaxter 1892 (Approved Lists 1980) strains were published previously (Stackebrandt et al., 2007). The patterns of the Myxococcus strains determined Morphological features of cells, swarms, myxospores and after propagation of the cells under the same conditions are fruiting bodies are as described by Reichenbach (2005b). listed in Supplementary Table S2. Branched fatty acids were Members of the genus do not decompose starch or xylan the predominant components in strains belonging to the on agar plates and do not hydrolyse aesculin. Variable for genus Myxococcus, headed by iso-C15 : 0 and iso-C17 : 0. The growth in the presence of 1.5 % NaCl. Sensitive to profiles included the hydroxylated acids iso-C14 : 0 3-OH kanamycin. Most strains are tolerant of 50 mg streptomy- 21 (1.4–10.4 %), iso-C15 : 0 3-OH (1.1–2.6 %) and iso-C17 : 1 3- cin sulphate l . Whole-cell fatty acid patterns have the OH (1.2–3.7 %). The following differences were found in following characteristics when grown on agar medium CY: comparison with the Corallococcus strains (excluding main components iso-C15 : 0 and C16 : 1v5c; contain no iso- Corallococcus macrosporus): C16 : 1v5c amounted for at least C14 : 0 but contain C16 : 1v11c; content of iso-C13 : 0 1.6 % or http://ijs.sgmjournals.org 2125 E. Lang and E. Stackebrandt

less, of summed feature 4 (including anteiso-C17 : 1) 7.4 % McCurdy, 1974), the eighth edition of Bergey’s Manual or less and of C16 : 1v5c at least 9.9 %. The G+C content of (Buchanan & Gibbons, 1974) combined members of the the DNA is 65–71 mol%. The type species is Myxococcus genera Myxococcus,‘Chondrococcus’ (including ‘Chondro- fulvus (Cohn 1875) Jahn 1911 (Approved Lists 1980). coccus macrosporus’) and Angiococcus in the genus Myxococcus, with several being listed as species incertae sedis. In drawing up the Approved Lists, Skerman et al. Emended description of the genus Corallococcus (1980) only took into consideration the placement of these Reichenbach 2007 species in the genus Myxococcus, and any other synonyms Morphological features of cells, swarms, myxospores and lost standing in nomenclature. However, Reichenbach & fruiting bodies are as described by Reichenbach (2005c). Dworkin (1981) decided to establish the genus Corallo- Members of the genus hydrolyse aesculin and decompose coccus informally for former members of the genus starch and xylan, producing large spots devoid of the ‘Chondrococcus’ Jahn 1924 including Corallococcus macro- hydrocarbons on agar plates. No growth in presence of sporus. Accordingly, Corallococcus macrosporus is listed as a 1.5 % NaCl. Sensitive to streptomycin. Some strains are member of the new genus Corallococcus (‘Chondrococcus’ tolerant of 250 mg kanamycin sulphate l21. Whole-cell Jahn 1924, 85) in the second edition of Bergey’s Manual of fatty acid patterns have the following characteristics: main Systematic Bacteriology (Reichenbach, 2005c). Besides components are iso-C15 : 0, anteiso-C17 : 1 and iso-C17 : 0; Corallococcus macrosporus, the genus contained Corallo- contain iso-C14 : 0 but no C16 : 1v11c, content of iso-C13 : 0 at coccus coralloides and the novel species Corallococcus least 2.7 % and of C16 : 1v5c 3.2 % or less. The G+C exiguus. The criteria for establishing a new genus distinct content of the DNA is 66–68 mol%. The type species is from Myxococcus were morphological, such as the cartila- Corallococcus coralloides (Thaxter 1892) Reichenbach 2007. ginous consistency of fruiting bodies, their bizarre shape and the large number of small fruiting bodies. T Typification of Myxococcus macrosporus and Because strain M271 (the designated type strain of Myxococcus stipitatus Myxococcus macrosporus) was not available, Reichenbach (2005c) designated a new strain as the type of Corallococcus Myxococcus stipitatus Thaxter 1897, with the type strain T T T macrosporus, strain Cc m8 (5DSM 14697 5CIP Windsor M78 , and Myxococcus macrosporus (Krzemie- 109128T). Hence, the names Corallococcus macrosporus niewska and Krzemieniewski 1926) Zahler and McCurdy T Reichenbach 2007 and Myxococcus macrosporus (Krzem- 1974, with the type strain Windsor M271 , were included ieniewska and Krzemieniewski 1926) Zahler and McCurdy on the Approved Lists of Bacterial Names (Skerman et al., 1974 (Approved Lists 1980) are based on different types. In 1980). The Approved Lists drew heavily on the eighth the footnotes supplementing Reichenbach (2007), it is edition of Bergey’s Manual of Determinative Bacteriology pointed out that Corallococcus macrosporus can not be a (Buchanan & Gibbons, 1974) as a source for locating new combination as cited in the effective publication for that suitable type material, as well as the source of many of the reason. On the other hand, there is little doubt species and genus descriptions. In this edition of Bergey’s (Reichenbach, 2005c) that the morphological and cultural T Manual, strain Windsor M78 is referred to as a reference properties of isolate Cc m8T match those of the original strain of Myxococcus stipitatus Thaxter 1897, while description/illustration of Krzemieniewska & Krzemienie- Myxococcus macrosporus is typified by the work of wski (1926) and are consistent with the description of Krzemieniewska & Krzemieniewski (1926), and strain Myxococcus macrosporus given in the eighth edition of T M271 is referred to as a reference strain. Despite the fact Bergey’s Manual by Zahler & McCurdy (1974). The results that these two strains became the type strains of these presented above support the view that strains classified in species on the Approved Lists, the term ‘reference strain’ the species Corallococcus macrosporus on morphological rather than ‘type strain’ was used for these organisms in the grounds, including strain Cc m8T, should be regarded as first edition of Bergey’s Manual of Systematic Bacteriology members of the genus Myxococcus. Even with respect to (Brockman, 1989). morphological criteria, Reichenbach (2005c) states in the While the genus affiliation of M. stipitatus has not been original description that Corallococcus macrosporus may be changed over decades, the taxonomic history of M. confused with strains of Myxococcus virescens. macrosporus is chequered. The species was originally placed It should be noted that the designated type strain in the genus ‘Chondrococcus’ (Jahn, 1924) as ‘Chondro- of Myxococcus macrosporus (Krzemieniewska and coccus macrosporus’ by Krzemieniewska & Krzemieniewski Krzemieniewski 1926) Zahler and McCurdy 1974, strain (1926) and retained, though illegitimate (the name has Windsor M271T, does not appear to be available and could previously been used for an alga; Jeffers & Holt, 1961), in not be included in these studies. However, it is clear that this genus until the seventh edition of Bergey’s Manual Reichenbach (2005c) considers Corallococcus macrosporus (Breed et al., 1957). When the taxonomic importance of and Myxococcus macrosporus to be synonyms, despite the the consistency of slime of fruiting bodies (firm in strains fact that two different types have been designated. If the of the genus ‘Chondrococcus’, while deliquescent in strains species Corallococcus macrosporus was to be considered to of the genus Myxococcus) was disregarded (Zahler & be a heterotypic synonym of Myxococcus macrosporus and

2126 International Journal of Systematic and Evolutionary Microbiology 59 Request for an Opinion be placed properly in the genus Myxococcus, the type of Acknowledgements Myxococcus macrosporus would be strain M271T, a rather We are grateful to B. J. Tindall for constructive hints and discussions undesirable state of affairs. concerning bacteriological nomenclature in this special case, to J. P. The situation is best solved by a Request for an Opinion Euze´by for his comments and to H. Reichenbach for valuable discussions and insights in myxobacterial . We wish to regarding the proposal that the type of Myxococcus thank to R. M. Kroppenstedt, M. Jando and G. Po¨tter for carrying out macrosporus be represented by a neotype, strain Cc m8 the fatty acid analyses and S. Welnitz and M. Kopitz for excellent (deposited as DSM 14697 5CIP 109128). Since this strain technical assistance. is already the type of Corallococcus macrosporus,a consequence of this action would be that the names Corallococcus macrosporus and Myxococcus macrosporus References should be considered to be homotypic synonyms, as Breed, R. S., Murray, E. G. D. & Smith, N. R. (editors) (1957). Bergey’s originally intended by Reichenbach (2005c). We consider Manual of Determinative Bacteriology, 7th edn. Baltimore: Williams & that Corallococcus macrosporus is a member of the genus Wilkins. Myxococcus and, as already pointed out above, the Brockman, E. R. (1989). Genus Myxococcus Thaxter 1892, 403AL.In description of Corallococcus macrosporus provided by Bergey’s Manual of Systematic Bacteriology, vol. 3, pp. 2144–2148. Reichenbach (2005c) demonstrates that the proposed Edited by J. T. Staley, M. P. Bryant, N. Pfennig & J. G. Holt. neotype strain Cc m8 agrees closely with the descriptions Baltimore: Williams & Wilkins. given by Krzemieniewska & Krzemieniewski (1926) and Buchanan, R. E. & Gibbons, N. E. (editors) (1974). Bergey’s Manual of Zahler & McCurdy (1974). Determinative Bacteriology, 8th edn. Baltimore: Williams & Wilkins. De Soete, G. (1983). A least squares algorithm for fitting additive trees to proximity data. Psychometrika 48, 621–626. Properties of Myxococcus macrosporus strain Felsenstein, J. (1993). PHYLIP (phylogeny inference package) version Cc m8 (5DSM 14697) 3.5.1. Distributed by the author. Department of Genome Sciences, Morphology of vegetative cells and swarms as described by University of Washington, Seattle, USA. Reichenbach (2005c). Does not decompose starch, xylan or Hook, L. A., Larkin, J. M. & Brockman, E. R. (1980). Isolation, aesculin. Grows in presence of 1.5 % NaCl. Resistant to characterization, and emendation of description of Angiococcus 50 mg streptomycin sulphate l21; sensitive to 250 mg disciformis (Thaxter 1904) Jahn 1924 and proposal of a neotype strain. Int J Syst Bacteriol 30, 135–142. kanamycin sulphate l21. Fatty acid profile contains iso- C as the main component; C v5c amounts to Jahn, E. (1924). Beitra¨ge zur botanischen Protistologie.I.Die 15 : 0 16 : 0 Polyangiden. Leipzig: Gebru¨der Borntraeger (in German). 18.1 %, anteiso-C17 : 1 to 1.9 %, C16 : 0v11c to 1.3 % and iso- C to 0.6 %. Jeffers, E. E. & Holt, J. G. (1961). The nomenclatural status of the taxa 13 : 0 of the Myxobacterales (Schizomycetes). Int Bull Bacteriol Nomencl A similar situation is seen with Myxococcus stipitatus. Taxon 11, 29–61. BecauseoftheunavailabilityofthetypestrainWindsor Ka¨mpfer, P. & Kroppenstedt, R. M. (1996). Numerical analysis of fatty M78T, Reichenbach (2005b) designated a new type strain acid patterns of coryneform bacteria and related taxa. Can J Microbiol Mx s8 rather than proposing that a neotype be 42, 989–1005. designated. Here, we request an Opinion to the effect Krzemieniewska, H. & Krzemieniewski, S. (1926). Miksobakterje that strain Mx s8 (5DSM 14675 5JCM 12634) serve as Polski (Die Myxobakterien von Polen). Acta Soc Bot Polon 4, 1–54 (in Polish with German abstract). the neotype strain for Myxococcus stipitatus. The descrip- tion of Myxococcus stipitatus provided by Reichenbach Ludwig, W., Strunk, O., Westram, R., Richter, L., Meier, H., Yadhukumar, Buchner, A., Lai, T., Steppi, S. & other authors (2005b) demonstrates that the proposed neotype strain (2004). ARB: a software environment for sequence data. Nucleic Acids agrees closely with the descriptions given by Thaxter Res 32, 1363–1371. (1897) and Zahler & McCurdy (1974). We are aware that Maidak, B. L., Olsen, G. J., Larsen, N., Overbeek, R., McCaughey, in both cases the designation of a neotype strain can only M. J. & Woese, C. R. (1997). The RDP (Ribosomal Database Project). become effective 2 years after publication of this Nucleic Acids Res 25, 109–111. proposal. Olsen, G. J., Matsuda, H., Hagstrom, R. & Overbeek, R. (1994). fastDNAml: a tool for construction of phylogenetic trees of DNA sequences using maximum likelihood. Comput Appl Biosci 10, 41–48. Properties of Myxococcus stipitatus strain Mx s8 Reichenbach, H. (2005a). Order VIII. Myxococcales Tchan, Pochon (5DSM 14675) and Pre´vot 1948, 398AL.InBergey’s Manual of Systematic Bacteriology, 2nd edn, vol. 2, part C, pp. 1059–1072. Edited by D. J. Brenner, N. R. Morphology of vegetative cells, swarms, fruiting bodies and Krieg, J. T. Staley & G. M. Garrity. New York: Springer. myxospores as described by Reichenbach (2005b). Does Reichenbach, H. (2005b). Genus I. Myxococcus Thaxter 1892, 403AL. not decompose starch, xylan or aesculin. Grows in the In Bergey’s Manual of Systematic Bacteriology, 2nd edn, vol. 2, part C, presence of 1.5 % NaCl. Resistant to 50 mg streptomycin pp. 1074–1079. Edited by D. J. Brenner, N. R. Krieg, J. T. Staley & G. 2 2 sulphate l 1; sensitive to 250 mg kanamycin sulphate l 1. M. Garrity. New York: Springer. Main fatty acids are iso-C15 : 0 (34.6 %), C16 : 1v11c Reichenbach, H. (2005c). Genus II. Corallococcus gen. nov. (16.0 %), iso-C17 : 0 (12.8 %) and C16 : 0 (10.7 %). (Chondrococcus Jahn 1924, 85). In Bergey’s Manual of Systematic http://ijs.sgmjournals.org 2127 E. Lang and E. Stackebrandt

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