INTERNATIONALJOURNAL OF SYSTEMATICBACTERIOLOGY, Jan. 1989, p. 1-6 Vol. 39, No. 1 0020-7713/89/010001-06$02.OO/O Copyright 0 1989, International Union of Microbiological Societies

Transfer of Pimelobacter tumescens to gen. nov. as Terrabacter tumescens comb. nov. and of Pimelobacter jensenii to as Nocardioides jensenii comb. nov. M. D. COLLINS,l M. DORSCH,’ AND E. STACKEBRANDT’” Department of Microbiology, Agricultural Food Research Council, Institute of Food Research, Reading Laboratory, Shinjield, Reading RG2 9AT, United Kingdom,’ and Institut fur Allgemeine Mikrobiologie, Christian-Albrechts- Universitat, 2300 Kiel, Federal Republic of Germany’

The phylogenetic interrelationship of members of the genera Nocardioides and Pimelobacter were examined by using reverse transcriptase sequencing of 16s ribosomal ribonucleic acid. The sequence studies demon- strated that Nocardioides albus, , Pimelobacter jensenii, and Pimelobacter simplex represent a coherent phylogenetic group at the genus level, whereas Pimelobacter tumescens occupies a separate line of descent. On the basis of sequence data and the chemotaxonomic distinctiveness of the latter organism, we propose that Pimelobacter tumescens be reclassified in a new genus, Terrabacter, as Terrabacter tumescens comb. nov.

Arthrobacter simplex and tumescens are mycelium), and its placement within the genus Nocardioides among the few named of coryneform which has been questioned (14). contain cell wall peptidoglycans based on ~~-2,6-diaminopi- 16s ribosomal ribonucleic acid (rRNA) cataloging shows melic acid (5, 16). The two species thus differ in peptidogly- that P. simplex is well removed from the arthrobacters sensu can composition from Arthrobacter globiformis, the type strict0 and indicates that this species occupies a line of species of the genus, which contains lysine as the dibasic descent the branching point of which is as low as that of amino acid (16). Although there is now general agreement other major lines within the actinomycetes (18, 19). To date that these species should be removed from the genus Arthro- comparative sequencing studies with other members of bacter, their taxonomic position remains controversial (10). Pimelobacter and Nocardioides have not been made. There- Suzuki and Komagata (19) proposed the creation of a new fore, in an attempt to clarify the relationship of P. simplex to genus, Pimelobacter, to accommodate these species. A third the genus Nocardioides and to resolve the position of P. species, Pimelobacter jensenii, was also proposed for an tumescens, we analyzed and compared long stretches of the atypical A. simplex strain (19). However, there is evidence 16s rRNA primary structures of these taxa. of considerable chemical heterogeneity within the genus Pimelobacter (3, 12, 19). Pimelobacter (Arthrobacter) sim- plex and P. jensenii are unusual among coryneform and MATERIALS AND METHODS related bacteria in producing complex mixtures of straight- Cultures and cultivation. Type strains Nocardioides albus chain saturated, monounsaturated, and anteiso-, and iso-, DSM 43109, Nocardioides luteus NCIB 11455, P. jensenii 10-methyl branched fatty acids (3, 12, 19-21). However, DSM 20641, P. simplex NCIB 8929, and P. tumescens NCIB Pimelobacter tumescens differs from these species in lacking 8914 were grown in shake flasks (casein peptone, 10 g; yeast 10-methyl branched acids and in containing substantial lev- extract, 5 g; glucose, 5 g; NaCl, 5 g; water, 1 liter; pH 7.4) to els (ca. 20%) of monounsaturated terminally branched acids late exponential phase at 25°C. (3). P. simplex and P. jensenii also differ from P. tumescens Sequence determination and analysis. Crude ribonucleic in synthesizing 2-hydroxylated long-chain fatty acids (3, 12). acid was isolated as described previously (7). Reverse tran- The polar lipid compositions of these taxa are also quite scriptase sequencing of ribonucleic acid was achieved by different. P. simplex and P. jensenii possess diphospha- using the method of Lane et al. (11). The sequence of tidylglycerol, phosphatidylglycerol, and hydroxyphospha- oligonucleotide primers, their target sites, and the electro- tidylglycerol (3, 12, 21). However, P. tumescens lacks phoretic separation conditions used for complementary de- hydroxyphosphatidylglycerol and in addition synthesizes oxyribonucleic acid have been described by Embley et al. two unknown aminophosphoglycolipids (3, 12). Such major (7). Some sequence ambiguities were resolved by using differences in lipid composition between P. simplex and P. terminal transferase (6). Sequence data were aligned and jensenii on the one hand and P. tumescens on the other hand homology values were determined with the Beckman Micro- indicate that these taxa should probably not be accommo- genie program (15). Calculation of evolutionary distance dated in the same genus. Interestingly, the lipid composition values (Knuc) and construction of phylogenetic trees fol- of P. simplex and P. jensenii is indistinguishable from that of lowed previously published procedures (8, 9). members of the genus Nocardioides (3, 12). Indeed, primar- ily on the basis of similarity in lipid composition, O’Donnell et al. (12) proposed that P. simplex be transferred to the RESULTS AND DISCUSSION genus Nocardioides. However, P. simplex does not possess a nocardioform morphology (extended primary and aerial The partial reverse transcriptase sequences of the five strains investigated are shown aligned in Fig. 1. The homol- ogy and derived K,,, values from 1,449 bases used for * Corresponding author. determining intragroup relationships are shown in Tables 1

1 2 COLLINS ET AL. INT. J. SYST.BACTERIOL.

f Na1 UCAAC~~A~A~UUUGAUCCU~~CUCA~~AC~AAC~C~~ACACAU~CMWC~A~C~~AAA~~UC~~..66C6AAC666U6A6UAACAC6U6A6UAAUC;16CCCCA66C Nl u UCMC66A6A6UUU6AUCCU66CUCA66AC6AAC6CU66C66C6U6CUUA~C1CAU6CAA6UC6~C66AAA66nnC6rn .66C6AAC666U6A6UAllCAC6U6A WAAUCU6CCCCffi6C Psi CUUAU66AGAGUUUUAUCCUU6CUCA66AC6AAC~UU6.66C6AAC666U6ffiUAAC~6U6AWnA~~CCCUnnnC P 1e UCAAC66A6A6UUU6AUCCU66CUCA66~6AAC6CU66C66C6U6CUUA~AC~~AA6UC~C66UAA66CUCU..66C6AllC666U646UAACnCGUGAGCMUCU6CCCUUCnC Pt u UCAAC66A6A6UUU6AUCCU66CUCA66AC6AAC6CUn6C66C6U6CUUAAC~AU6CllA6UC6AAC66U6AC6AUCA.,66C6MC666U6A6UAACAC6U~WA~nCUGCCCCAGIIC

Ma1 UnU666AUA6CCACC66AAAC66UnAUUAAUACCGCAUIlCGACAIICCGAUUGCAUnlUlCUn6Un6U66AAA6WUW C66CCU1)66AU6U6CUC6C66CCUAUCA6CUUW~W6A~ MIu U~U~~~~UA~CCACC~~AAAC~~UGAUUAAUACC~CAUAC~ACAACC~AUU~CAU~AUCU~~UU~U~~~A~WWU C66CCU666AU6U6CUC6C6GCCUAUCA6CW6UU6W6A~ Psi UCu666AUA6CCACC6~AAC66U6AUUAAUACC66AUAU6ACCACUCUA66CAUCAU6U66Un6U66AAffi~UUUC66UCC~66AU6U6CUC6C6GCCUAUCA6CUnGUU66UGA66 P J e UUU666AUC\ACUBCC66AAAC66UnGCUAA~CC~4U~6C\CCI\66 Pt u UCU666AUMCCCC666AAACC66A6CUAAUACC66AUAU6ACACCA6CC~CAU666C~~6U~~~6W UUU C66UCU66611U66ACUn6C66CCUA~~UU6UU66U66

Ma1 UAAU66CUCACCAA66CUUC6AC666UA6CC66CCU6A6A66W6ACC66CC~~~66ACU6A6ACAC~CCCA~CUCCUAC666~6CffiCAW66~AAUAW66ACAAU666C6 N 1 u UAAU66CUCACCAA66CUUC6AC666UA6CC66CCU6116A666U6ACC66CCACACU66W666611AUWU66ACAAfi66C6 PSI UAAU66CUCACCAA66CUnU6AC666UA6CC66CW6A6A66W6ACC66CCACICWiC6 Pje UAAU66CUCACCAA66CUUC6AC666UA6CC66CCU6A6A666U~CC66CCC1CAC~~~UGA6~AC66CCCA6ACUCCUAC666A66CA6CAW6666AA~UU~AC~U666C6 P t u UA6U66CUCACCC1a66C6AC6~666UC16Cn66CCU6A6A666C6ACC66~~C1CU6~ACU6ffiACC1C66CCC~~CUCCUAC666~6CA6CA6~666MUAW6CACMU666C6

Nal 6AA6CCUnAUCCA6CA~6CC6C6U6A666~6AC66CCUnC666UU6UAMCCUCUUUCA6C~CA6AC6~A6C6AAA6U6AC6~AU6U~A6AA6AA66ACC66CCAACUACW6CCA N1 u 6AA6CCUnAUCCA6C#AC6CC6C6U6A666AU6AC66CCUUC666UU6UAMCCUCWUCA6CIC16AC6~A~6C~A6U~C6WAU6U6Cffi~~6A~6ACC66CC~CUACWGCCA Psi 6AA6CCUnAUCC~6CAAC6CC6C6U6A666AU6AC66CCUUC666UUGUAAACCUnUUUCA6UACC6AC6AA6C6AAA6U6AC6WA6WAC116AA6AA66ACC66CCAACUAC6U6CCA Pie AAA6CCUn4UCCA6CAAC6CC6C6UGA666AU6AC66CCUnC666UU6UARACCUCUUUCA6C6666AC6AA6C61M6U6AC66UAC~6C~AA~~6CACC66CC~CU~W6CCA Pt u AAII6CCUn ~6CffiC6AC6CC6C6U6A666AU6AC66CCUUC666UU6UAAACCUCUUUC16CA666AA6AA6C6AA~6U6AC66UACCU6CA6AA~A6CACC~CU11ACUAC6U6CCA

Nal 6C~CC6C66UAAUAC6UA666UCCUffiCCW~CC66MUUAUU666C6UAAA666CUU6U~6Cn6UnU6UC6CWC666A6U6AAMCCA66U6CUUAACACCUnGCCUnCUUCC6A Nlu 6CA6CC6C66UAAUAC6UA666UCCUA6CCUUAUCC66AAWAUU666C6U~AA666CUU6UA66Cn6UnU6UC6C6UC66An6ffi~AAACCA6$UGCWAACACCUn~CU6CUUUC~ Psi 6CA6CC6C66UAAUAC6U~66UCCn46CnUUnUCC66n6UnU6UC6C6UCn6nn6U6AAAACC666n6CUU~CU6nU6CUU6CUUUC6n Pie 6CA6CC6C66UAAUAC6UA666UCCn~6C6WAUCC66AAUUWU666C6UAAA~6CUC6UA66CC6UnU6UCAC6UC666A6U6AAMCCA66U6CUUAACACCUnGCCU6CUUCC6A Ptu 6Cn6CC6C66UAAUAC6UA666U6CnA6C6UU6UCC66ARUUAnU666C6UAAA6A6CUn6nA66U66UUn6UC6C6UCU6CU6U6AAAAUCC6A66CUCAACCUC66ACUn6Cn611666

Nal UAC666CA6ACUn6A66U~~A6666A6A~U66AAUUCC~6U6UA6C66~AAAU6~CA6AUAUCA66A66AACllCC~UG6C6AA66C66WCUCU~6A~AU~CUnAC6CU6~ N1 u UAC666CA611CUn6A66UACUCA6666A6A~66MUUCCU66U6UA6C66U6nAA~C6CA6AUAUCA66A~AACACC~U6~6AA66C66UUCUCU~6A6~UCCUnAC6C~A6 Psi UAC666CA6ACUn6A66UAU6CA6666A6A~66~AUUCCU66U6UA6C66U6ll11AU6C6CA6AUA~A66A66AACACC66U66C6AC166C66UUCUCU666CAUUllCCUnAC6CU6A6 Pje UAC666CA6ACUn6A66UIIn6Cn6666A6~AC66~AUUCCUn6U6U~C66U6AAA~C6CA6AUAUCA66A66~ACACC66U6~6A~6C66UUCUCU666CAUUACCUnAC6CU6A6 Ptu UAC666CA6ACUn6A6U6U66UA6666A6ACU66~AUUCCU66U6UA6C66066ACIU6CA6AUAUC~6A66AACACC6A~6C6AA66CA66UCUCU666CUAUUACU6AC6CU6A6

Nal 6A6C6AAA6U6U6666A6C6AACA66AUUA6AUACCCU66UA~CCACACC6UAAAC6W666C6CUA66U6U666ACACAUUCCAC6UnUUCC6U6CC6CA6CUAAC6CAU~A6C6CC N1 u 6A6C6A~A6U6U6666A6C6AACA66~UUA~UACCCU66UA6UCCACACC6UAAAC6~6~6CUA66U6U666AUCCAU\tlUCAC66nUUCC6U6CC6CAGCUAAC6CAUUAA6C6CC Psi 6A6C6AAA6U6U6666A6C6MCA66AUUA6AUACCCU66UA6UCCACACCWAAAC6U~66C6CUA66U6U6666UCCWUCCAC66AUUCC6UGCC6UA6CUIIAC6CAUUAA6C6CC Pie 6A6C6AAA6U6U6666A6C6~ACA66AUUA6AUACCCU66UAGUCCAC~C6UAA~C6W666C6CUA66U6U666ACUnAUUCCAC6ffiUUCC6U6CC6CA6CUAAC6CAUUAA6C6CC Ptu AA6C6~AA6Cl\U6666A6C64ACA66AUUA6AUACCCU66U~6UCCAU6CC6UAAAC6UU666AACUA66U6U666UCUn~UUCCnC6A6AUCC6U6CC6CA6CUAAC6CAUUAA6UUCC and 2. The philogenetic tree derived from the latter values is lines (i.e., Streptoverticiflium, Frankia, Actinomyces, Pro- depicted in Fig. 2. The two Nocardioides species which we pionibacterium , Pseudonocardia , Bifidobacterium , and my- examined possess very high sequence homology (>98%). P. colic acid-containing taxa). It is evident from both trees that simplex and P. jensenii also share a relatively high level of P. tumescens is only loosely related to P. simplex, P. homology (ca. 95%) and are approximately equidistant from jensenii, N. albus, and N. luteus, forming an individual each other and Nocardioides species. P. tumescens displays subline. significantly lower levels of homology to these species (ca. The high levels of sequence homology among N.albus, N. 90%). To ascertain the intergroup relationships, the se- luteus, P.jensenii, and P. simplex are in accordance with the quences of the species described above were compared with high degree of chemical similarity among these species (3, those of 18 previously studied actinomycetes from 14 genera 12) and the results of phage typing (13). These data strongly (2, 4, 7; E. Stackebrandt, J. Smida, and M. D. Collins, J. support the union of Nocardioides and Pimelobacter into a Gen. Appl. Microbiol., in press; J. Smida, T. M. Embley, single genus, for which Nocardioides has priority (by date of M. D. Collins, D. Hahn, and E. Stackebrandt, unpublished publication). The inclusion of P. simplex and P. jensenii in data). The latter comparison was based on 480 nucleotides the genus Nocardioides makes the latter heterogeneous with involving only variable positions between points 200 and respect to morphology. However, there is now evidence that 1,435 (Escherichia coli numbering system 111). Repre- morphological characters are not reliable indicators of relat- sentative homology values are shown in Table 1. The edness (17, 18). The degree of morphological differences branching pattern (Fig. 3) indicates that all Nocardioides among these taxa is in any case debatable. Prauser (13) noted spp. and pimelobacters constitute a separate line of descent, that strain IMET 7801, initially intended to be the type strain comparable in phylogenetic depth to the depths of the major of N. albus, lost the ability to form aerial mycelium on VOL. 39, 1989 TERRABACTER GEN. NOV. 3

Ha 1 N1 u Psi P3e Pt u

Ya 1 N1 u Psi P je Pt u Ha 1 Nlil Psi fs je Ptil

Hal N1 u Psi P je Ptu Nal N1 u Psi Pje Ftu

Nal 6CU66C6AU N1 u SCU66C6AU Ps 1 GCU66C6AU PIP 6CU66C6AU fitu cIC1166C6BU FIG. 1. Partial 16s rRNA sequences of N. albus (Nal), N. luteus (Nlu), P. jensenii (Pje), P. simplex (Psi), and P. tumescens (Ptu). The dots indicate an unsequenced region of 18 nucleotides. n, Undetermined nucleotide. A space indicates a nucleotide gap. The asterisk at the 5' terminus corresponds to position 1, and the last base at the 3' terminus corresponds to position 1,497 of the E. coli sequence (1). continued subculture. Furthermore, Nocardioides species tumescens has been shown to be quite different from the exhibit a developmental cycle in which with increasing age latter two species (3). In view of the isolated phylogenetic the substrate mycelium fragments into irregular rod-shaped position of P. tumescens, together with its chemical distinc- to coccoid elements, giving the appearance of coryneform tiveness, we suggest that this organism be reclassified in a morphology. Therefore, we consider the morphological ob- new genus, Terrabacter, as Terrabacter tumescens comb. jections insufficient grounds for retaining the separateness of nov. these genera. We concur with the proposal of O'Donnell et Description of Nocardioides jensenii (Suzuki and Komagata) al. (12) to reclassify P. simplex as Nocardioides simplex and comb. nov. The description below is based on data from also propose the new combination Nocardioides jensenii. references 3 and 17. A rod-coccus growth cycle occurs The ribonucleic acid studies do not support the suggestion of during growth on complex media. Exponential-phase cells Suzuki and Komagata (19) that P. tumescens, P. simplex, are long, irregular rods (ca. 0.6 to 1.0 by 2.0 to 7.0 pm). and P. jensenii should be included in the same genus. P. Older cultures are composed of coccoid cells. Aerial myce-

TABLE 1. K,,, values for Nocur-dioides and Pirnelobacter species K,,, value with:b Strain" Pimelobacter jensenii Pimelobacter tumescens Nocurdioides albus Nocardioides luteus DSM 29641" NCIB 8914T DSM 431WT NCIB 114ST Pimelobacter simplex NCIB 8929T 0.122 (0.091) 0.214 (0.101) 0.112 (0.059) 0.107 (0.058) Pimelobacter jensenii DSM 29641T 0.201 (0.087) 0.093 (0.057) 0.117 (0.054) Pirnelobacter tumescens NCIB 8914T 0.230 (0.109) 0.231 (0.101) Nocardioides albus DSM 43109T 0.019 (0.015)

a NCIB, National Collection of Industrial Bacteria; DSM. Deutsche Sammlung von Mikroorganismen. * The values not in parentheses were calculated from 480 nucleotides. The values in parentheses were based on a comparison of 1,449 nucleotides. 4 COLLINS ET AL. INT. J. SYST.BACTERIOL.

Pime lobacter iso-, anteiso-, and 10-methyl-branched types; 2-hydroxy turnescens fatty acids are also produced. The polar lipids comprise diphosphatidylglycerol, phosphatidylglycerol, phosphatidyl- inositol, and hydroxyphosphatidylglycerol. The major iso- prenoid quinone is MK-8 (11,111-H4). The guanine-plus- cytosine content of the deoxyribonucleic acid is 68.8 mol% (thermal denaturation met hod). The type strain is strain NCIB 9770 (= JCM 1364 = DSM 20641). The description of the type strain corresponds to that of the species. Pimelobacter simp 1 ex Description of Terrabacter gen. nov. Terrabacter (Ter.ra. A bac’ter. L. n. terra, earth; M. L. masc. n. bacter, masc. Nocardioides h Nocardioides equivalent of Gr. neut. n. bacterum, a rod; Terrabacter, albus luteus earth [soil] rod). The description below is based on data from FIG. 2. Unrooted phylogenetic tree displaying the interrelation- references 3, 8, 10, and 17. A rod-coccus growth cycle ship of Nocardioides and Pimelobacter species. The branching occurs during growth in complex media. Irregular rods are pattern was derived from K,,, values (Table 1). Bar = 0.01 K,,, unit. observed in exponential-phase cultures; stationary-phase cultures are composed of mainly coccoid cells. Both rods and coccoid forms are gram positive. Cells are non-acid fast lium is not formed. Nonmotile. Colonies are glossy, smooth, and do not form endospores. Rods are nonmotile or occa- entire, and white. Growth in 5% NaCl but not 10% NaCl. sionally motile. Growth at 10 and 35°C. Optimum tempera- Does not grow at 37°C. Catalase positive. Oxidase negative. ture for growth, ca. 25 to 30°C. Does not survive heating at Nutritionally nonexacting; growth occurs in suitable mineral 63°C for 30 min. Growth in 5% NaC1. Catalase positive. salts medium with an ammonium salt or nitrate as the sole Oxidase negative. Obligately aerobic. Acid is not produced nitrogen source and glucose as the carbon-plus-energy from glucose and other sugars in peptone-based media. source. Acid is not produced from glucose and other sugars Cellulose is not hydrolyzed. Nitrate is reduced to nitrite. The in peptone-based media. A wide range of organic compounds cell wall peptidoglycan contains ~~-2,6-diaminopimelicacid are utilized as sole or principal carbon-plus-energy sources (variation A3y) as the diamino acid. Mycolic acids are for growth, including glucose, sucrose, L-rhamnose, and absent. The long-chain cellular fatty acids are primarily of acetate. Deoxyribonuclease is produced. Urease positive. the iso-methyl branched types; straight-chain saturated, Nitrate is reduced to nitrite. The cell wall peptidoglycan is anteiso-methyl branched, and monounsaturated iso-methyl based on ~~-2,6-diaminopimelicacid (type LL-A,pm-Gly,). branched acids are also present. The polar lipids comprise The nonhydroxylated long-chain fatty acids are complex, diphosphatidylglycerol,phosphatidylethanolamine, phospha- consisting of straight-chain saturated, monounsaturated, and tidylinositol, and some unknown amino-containing phospho-

Propionibacterium

P. P. N. N.

Bifidobacterium FIG. 3. Unrooted phylogenetic tree displaying the relationship of Nocardioides and Pimelobacter species to other reference actinomy- cetes. Bar = 0.04 K,,, unit. VOL. 39, 1989 TERRABACTER GEN. NOV. 5

Pimelobacter simplex NCIB 8929T

Pirnelobacter jensenii DSM 29641T

Pimelobacter tumescens NCIB 8914T

Nocardioides albus DSM 43109T

Nocardioides luteus NCIB 114ST

Bifidobacterium bijidum DSM 20456T

Streptoverticillium baldaccii DSM 40845T

Propionibacterium freudenreichii DSM 20271T

Actinomyces bovis DSM 43014T

Frankia sp. strain Ag45/Mut15

Mycobacterium tuberculosis H37lRV

Nocardia asteroides DSM 43005

Tsukamurella paurometabolum DSM 20162T

Rhodococcus erythropolis DSM 43188 6 COLLINS ET AL. INT. J. SYST. BACTERIOL. glycolipids. The major isoprenoid quinones are tetrahydro- composition of Arthrobacter simplex, Arthrobacter tumescens genated menaquinones with eight isoprene units [MK-8 and possibly related taxa. Syst. Appl. Microbiol. 4:18-26. (II,III-HJ]. The guanine-plus-cytosine content of the deoxy- 4. Collins, M. D., J. Smida, M. Dorsch, and E. Stackebrandt. 1988. ribonucleic acid is 69.8 to 73.4 mol% (thermal denaturation Tsukamurella gen. nov. harboring Corynebucteriurn paurome- tabolum and Rhodococcus aurantiacus. Int. J. Syst. Bacteriol. method). Phylogenetically, Terrabacter belongs to the acti- 38: 385-39 1. nomycetes subdivision, forming together with Nocardioides 5. Cummins, C. S., and H. Harris. 1959. Taxonomic position of a separate line of descent. The type species is Terrabacter Arthrobacter. Nature (London) 184:831-832. tumescens. 6. De Borde, D. C., C. W. Neave, M. L. Herlocher, and H. F. Description of Terrabacter tumescens (Jensen) comb. nov. Maassab. 1986. Resolution of a common sequencing ambiguity The description below is based on data from references 3,8, by terminal deoxynucleotidyl transferase. Anal. Biochem. 157: 10, and 17. In addition to the characteristics of the genus, the 275-282. salient characteristics are given below. A rod-coccus cycle 7. Embley, T. M., J. Smida, and E. Stackebrandt. 1988. Reverse occurs during growth on complex media. Cells from older transcriptase sequencing of 16s ribosomal RNA from Faenia r-ectivirgula, Pseudonocardia thermophila and Saccharopoly- cultures are coccoid (diameter, 0.5 to 0.8 pm). After transfer spora hirsuta, three wall type IV organisms which lack mycolic to fresh complex media long, irregular rods (0.6 to 1.2 by 2.0 acids. J. Gen. Microbiol. 134:961-966. to 6.0 pm) are formed. The long rods show primary branch- 8. Fitch, W. M., and E. Margoliash. 1967. Construction of phylo- ing. Aerial mycelium is not formed. Generally nonmotile genetic trees: a method based on mutation distances as esti- (occasionally motile strains occur). Colonies are glossy, mated from cytochrome c sequences is of general applicability. entire, smooth, and gray or white. Growth at 10 and 35°C; Science 155279-284. may or may not grow at 37°C. Optimum temperature for 9. Hori, H., and S. Osawa. 1979. Evolutionary change in 5s rRNA growth ca. 25 to 30°C. Most strains grow in 5% NaC1. secondary structure and phylogenetic tree of 54 5s rRNA Obligately aerobic. Acid is not formed from glucose and species. Proc. Natl. Acad. Sci. USA 76:381-385. other sugars in peptone-based media. Thiamine is the only 10. Keddie, R. M., M. D. Collins, and D. Jones. 1986. Genus Arthrobacter Conn and Dimmick 1947, p. 1288-1301. In growth factor required (when thiamine is provided, the P. H. A. Sneath, N. S. Mair, M. E. Sharpe, and J. G. Holt organism utilizes an ammonium salt or nitrate as the sole (ed.), Bergey’s manual of systematic bacteriology, vol. 2. The nitrogen source in mineral salts medium with glucose as the Williams & Wilkins Co., Baltimore. carbon-plus-energy source). A wide range of organic com- 11. Lane, D. J., B. Pace, G. J. Olsen, D. A. Stahl, M. L. Sogin, and pounds is utilized as sole or principal carbon-plus-energy N. R. Pace. 1985. Rapid determination of 16s ribosomal RNA sources for growth, including acetate, D-alanine, crotonate, sequences for phylogenetic analyses. Proc. Natl. Acad. Sci. inositol, a-D-glucosamine, D-mannose, and raffinose ; D- USA 82:6955-6959. glucuronate, L-ornithine, D-phenylalanine, and uric acid are 12. O’Donnell, A. G., M. Goodfellow, and D. E. Minnikin. 1982. Lipids in the classification of Nocardioides: reclassification of not utilized. Gelatin, hippurate, and tyrosine are hydrolyzed. Arthrobacter simplex (Jensen) Lochhead in the genus Nocar- Starch may or may not be hydrolyzed. Some strains hydro- dioides (Prauser) emend. O’Donnell et al. as Nocardioides lyze Tween 80. Deoxyribonuclease is produced. Urease and simplex comb. nov. Arch. Microbiol. 133:323-329. sulfatase negative. Some strains produce H2S. The guanine- 13. Prauser, H. 1976. Nocardioides, a new genus of the order plus-cytosine content of the deoxyribonucleic acid is 69.8 to Actinomycetales. Int. J. Syst. Bacteriol. 26:58-65. 72.4 mol% (thermal denaturation method). Occurs in soil. 14. Prauser, H. 1986. Genus Nocardioides Prauser 1976, p. 1481- The type strain is strain NCIB 8914 (= DSM 20308 = 1485. In P. H. A. Sneath, N. S. Mair, M. E. Sharpe, and J. G. ATCC 6947). In most respects the description of the type Holt (ed.), Bergey’s manual of systematic bacteriology, vol. 2. strain corresponds to that of the species. The type strain is The Williams & Wilkins Co., Baltimore. 15. Queen, C., and L. J. Korn. 1984. A comprehensive sequence nonmotile. Starch and Tween 80 are hydrolyzed. H2S is not analysis program for the IBM personal computer. Nucleic Acids produced. Res. 12581-599. 16. Schleifer, K. H., and 0. Kandler. 1972. Peptidoglycan types of ACKNOWLEDGMENTS bacterial cell walls and their taxonomic implications. Bacteriol. Rev. 36:407-477. E.S. was supported by the Gesellschaft fur Biotechnologische 17. Stackebrandt, E., and C. R. Woese. 1981. Towards a phylogeny Forschung for performing research of relevance for the Deutsche of actinomyetes and related organisms. Curr. Microbiol. 5197- Sammlung von Mikroorganismen, Braunschweig, Federal Republic 202. of Germany. M.D.C. is grateful to the Agricultural Food Research 18. Stackebrandt, E., and C. R. Woese. 1981. The evolution of Council, Institute of Food Research, Reading, United Kingdom, for prokaryotes, p. 1-31. In M. J. Carlile, J. F. Collins, and support of the visit to the laboratory of E.S. B. E. B. Moseley (ed.), Molecular and cellular aspects of mi- crobial evolution. Cambridge University Press, Cambridge. 19. Suzuki, K., and K. Komagata. 1983. Pimelobacter gen. nov., a LITERATURE CITED new genus of coryneform bacteria with LL-diaminopimelic acid Brosius, J., J. L. Palmer, J. P. Kennedy, and H. F. Noller. 1978. in the cell wall. J. Gen. Appl. Microbiol. 2959-71. Complete nucleotide sequence of a 16s ribosomal RNA gene 20. Yano, I., Y. Furukawa, and M. Kusunose. 1971. Fatty acid from Escherichiu coli. Proc. Natl. Acad. Sci. USA 754801- composition of Arthrobacter simplex grown on hydrocarbons: 4805. occurrence of 2-hydroxy-fatty acids. Eur. J. Biochem. 23:220- Charfreitag, D., M. D. Collins, and E. Stackebrandt. 1988. 228. Reclassification of Aruchnia propionica as Propionibacterium 21. Yano, I., Y. Furukawa, and M. Kusunose. 1971.2-Hydroxy fatty propionicus comb. nov. Int. J. Syst. Bacteriol. 38:354-357. acid containing phospholipid of Arthrobacter simplex. Biochim. Collins, M. D., R. M. Keddie, and E. Kroppenstedt. 1983. Lipid Biophys. Acta 210:105-115.