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Melanelixia and Melanohalea, two new genera segregated from Melanelia (Parmeliaceae) based on molecular and morphological data.

This paper continues a revision of generic concepts in the parmelioid lichens using molecular data in order to reach a consensus among lichenologists over which segregates proposed over the last two decades should be accepted. Here we employ data from three gene portions to provide a basis for a revised generic concept of the brown parmelioid lichens hitherto classified in Melanelia. The phylogeny was studied using a Bayesian analysis of a combined data set of nuclear ITS, LSU rDNA and mitochondrial SSU rDNA sequences. 173 new sequences were obtained from 38 specimens of 15 Melanelia species, 37 related parmelioid species, and eight non-parmelioid species. The results indicate that Melanelia is not monophyletic but falls into four different clades. The genus Melanelia is restricted here to a small group of saxicolous lichens related to the type species M. stygia, and with bifusiform conidia, while the remaining species, most of which are primarily corticolous and have mainly cylindrical to filiform conidia, belong to two other clades recognised as two new genera: Melanelixia and Melanohalea, to accommodate the M. exasperata and M. glabra groups, respectively. 27 new combinations are made. The epicortex of Melanelixia species have pores or special structures termed here 'fenestrations', while most Melanohalea species are pseudocyphellate. Pleurosticta links to the Melanohalea clade but without strong support, and the phylogenetic position of M. disjuncta and its related species remains uncertain, linking with the Xanthoparmelia (syn. Neofuscelia) clade but also without strong support.

Ascomycota↗

Proposal of the genus Sphingomonas sensu stricto and three new genera, Sphingobium, Novosphingobium and Sphingopyxis, on the basis of phylogenetic and chemotaxonomic analyses.

Phylogenetic analyses of 16S rRNA gene sequences by distance matrix and parsimony methods indicated that the currently known species of the genus Sphingomonas can be divided into four clusters. Some chemotaxonomic and phenotypic differences were noted among these clusters. Three new genera, Sphingobium, Novosphingobium and Sphingopyxis, are proposed in addition to the genus Sphingomonas sensu stricto. The genus Sphingobium is proposed to accommodate Sphingomonas chlorophenolica, Sphingomonas herbicidovorans and Sphingomonas yanoikuyae. The genus Novosphingobium is proposed for Sphingomonas aromaticivorans, Sphingomonas capsulata, Sphingomonas rosa, Sphingomonas stygia, Sphingomonas subarctica and Sphingomonas subterranea. Sphingomonas macrogoltabidus and Sphingomonas terrae are reclassified in the genus Sphingopyxis. The type species of Sphingobium, Novosphingobium and Sphingopyxis are Sphingobium yanoikuyae, Novosphingobium capsulatum and Sphingopyxis macrogoltabida, respectively.

Alphaproteobacteria↗

Re-examination and phylogeny of the genus Chondrostoma based on mitochondrial and nuclear data and the definition of 5 new genera.

Previous molecular phylogenetic studies of the genus Chondrostoma (Cyprinidae: Leuciscinae) were unable to resolve the relationship among its major species groups. In this paper we present a phylogeny for this genus, based on five mitochondrial genes and the nuclear gene beta-actin, comprising a total of 4068 bp. Bayesian inference using all gene fragments yielded a fully resolved phylogeny, compatible with topologies obtained from individual fragments using maximum parsimony and minimum evolution. Mapping of morphological characters critical to the rasping feeding mode of most Chondrostoma species indicates that they evolved several times, and questions the use of these characters in the traditional definition of the genus. Our findings led us to the definition of the following new genera: Achondrostoma, Iberochondrostoma, Pseudochondrostoma, Protochondrostoma and Parachondrostoma. Our data contradict the hypothesis of a rapid radiation during Lago Mare phase, suggested by previous studies.

Actins↗

Proposal for two new genera, Brevibacillus gen. nov. and Aneurinibacillus gen. nov.

16S rRNA gene sequences of the type strains of 11 species belonging to the Bacillus brevis and Bacillus aneurinolyticus groups were determined. On the basis of the results of gene sequence analyses, these species were separated into two clusters. The B. brevis cluster included 10 species, namely, Bacillus brevis, Bacillus agri, Bacillus centrosporus, Bacillus choshinensis, Bacillus parabrevis, Bacillus reuszeri, Bacillus formosus, Bacillus borstelensis, Bacillus laterosporus, and Bacillus thermoruber. Bacillus aneurinolyticus and Bacillus migulanus belonged to the B. aneurinolyticus cluster. Moreover, the two clusters were phylogenetically distinct from other Bacillus, Amphibacillus, Sporolactobacillus, Paenibacillus, and Alicyclobacillus species. On the basis of our data, we propose reclassification of the B. brevis cluster as Brevibacillus gen. nov. and reclassification of the B. aneurinolyticus cluster as Aneurinibacillus gen. nov. By using 16S rRNA gene sequence alignments, two specific PCR amplification primers were designed for differentiating the two new genera from each other and from other aerobic, endospore-forming organisms.

Bacillus↗

Proposal of the genus Thermoactinomyces sensu stricto and three new genera, Laceyella, Thermoflavimicrobium and Seinonella, on the basis of phenotypic, phylogenetic and chemotaxonomic analyses.

Phylogenetic analysis based on 16S rRNA gene sequences revealed that Thermoactinomyces species with validly published names can be assigned to four clusters or lineages. The type strains of Thermoactinomyces sacchari and Thermoactinomyces putidus were differentiated from the type strains of Thermoactinomyces vulgaris and Thermoactinomyces intermedius by the predominant menaquinone and fatty acid profiles. The type strains of Thermoactinomyces dichotomicus and Thermoactinomyces peptonophilus formed lines of descent distinct from other Thermoactinomyces species. Thermoactinomyces dichotomicus KCTC 3667T was distinguishable from the type strains of Thermoactinomyces vulgaris and Thermoactinomyces intermedius by the contents of two fatty acids, iso-C(16 : 0) and iso-C(17 : 0). Thermoactinomyces dichotomicus could be distinguished from other Thermoactinomyces species by DNA G+C content and some phenotypic properties, particularly its property of forming a yellow colour. The type strain of Thermoactinomyces peptonophilus was distinguishable from other Thermoactinomyces species by differences in menaquinone profile, major fatty acids, DNA G+C content and some physiological properties including optimal growth temperature. On the basis of these data, the creation of three new genera, Laceyella, Thermoflavimicrobium and Seinonella, is proposed in addition to the genus Thermoactinomyces sensu stricto. The genus Laceyella gen. nov. is proposed to accommodate Thermoactinomyces sacchari and Thermoactinomyces putidus as Laceyella sacchari comb. nov. and Laceyella putida comb. nov., the genus Thermoflavimicrobium gen. nov. is proposed for Thermoactinomyces dichotomicus as Thermoflavimicrobium dichotomicum comb. nov. and the genus Seinonella gen. nov. is proposed for Thermoactinomyces peptonophilus as Seinonella peptonophila comb. nov.

Bacillaceae↗

The phylogenetic relationships of the hat-shaped ascospore-forming, nitrate-assimilating Pichia species, formerly classified in the genus Hansenula Sydow et Sydow, based on the partial sequences of 18S and 26S ribosomal RNAs (Saccharomycetaceae): the proposals of three new genera, Ogataea, Kuraishia, and Nakazawaea.

The twenty-seven strains of the hat-shaped ascospore-forming, nitrate-assimilating species, formerly classified in the genus Hansenula, of the genus Pichia were examined for their 18S and 26S rRNA partial base sequencings. All the strains examined were separate phylogenetically from the type strain of P. membranaefaciens (type species of genus Pichia). Based on the sequence data obtained [by number of base differences (five or more) with P. anomala and base sequences on fingerprint segment] in the 18S rRNA partial base sequences, these species were divided into seven groups. Group I, including P. anomala (identical to H. anomala, type species of genus Hansenula), P. canadensis, P. muscicola, P. silvicola, P. subpelliculosa, P. americana, P. bimundalis, P. ciferrii, P. syndowiorum, P. bispora, and P. fabianii, corresponded to the genus Hansenula Sydow et Sydow. Groups II and III were comprised of P. capsulata and P. holstii, respectively. Group IV included P. angusta, P. minuta var. minuta, P. minuta var. nonfermentans, P. philodendra, P. glucozyma, and P. henricii. Groups V, VI, and VII included P. jadinii, P. petersonii, and P. dryadoides, respectively. The nitrate assimilation-negative species, P. wickerhamii was phylogenetically distant from P. membranaefaciens. The seven groupings are discussed phylogenetically and taxonomically. For Groups IV, II, and III, the three new genera were proposed as Ogataea, Kuraishia, and Nakazawaea, respectively, with the type species, O. minuta (identical to P. minuta), K. capsulata (identical to P. capsulata), and N. holstii (identical to P. holstii).

Base Sequence↗

Phylogenetic relationships among the Chromatiaceae, their taxonomic reclassification and description of the new genera Allochromatium, Halochromatium, Isochromatium, Marichromatium, Thiococcus, Thiohalocapsa and Thermochromatium.

Sequences of the 16S rDNA from all available type strains of Chromatium species have been determined and were compared to those of other Chromatiaceae, a few selected Ectothiorhodospiraceae and Escherichia coli. The clear separation of Ectothiorhodospiraceae and Chromatiaceae is confirmed. Most significantly the sequence comparison revealed a genetic divergence between Chromatium species originated from freshwater sources and those of truly marine and halophilic nature. Major phylogenetic branches of the Chromatiaceae contain (i) marine and halophilic species, (ii) freshwater Chromatium species together with Thiocystis species and (iii) species of the genera Thiocapsa and Amoebobacter as recently reclassified [Guyoneaud, R. & 6 other authors (1988). Int J Syst Bacteriol 48, 957-964], namely Thiocapsa roseopersicina, Thiocapsa pendens (formerly Amoebobacter pendens), Thiocapsa rosea (formerly Amoebobacter roseus), Amoebobacter purpureus and Thiolamprovum pedioforme (formerly Amoebobacter pedioformis). The genetic relationships between the species and groups are not in congruence with the current classification of the Chromatiaceae and a reclassification is proposed on the basis of 16S rDNA sequence similarity supported by selected phenotypic properties. The proposed changes include the transfers of Chromatium minus and Chromatium violascens to Thiocystis minor comb. nov. and Thiocystis violascens comb. nov., of Chromatium vinosum, Chromatium minutissimum and Chromatium warmingii to the new genus Allochromatium as Allochromatium vinosum comb. nov., Allochromatium minutissimum comb. nov., and Allochromatium warmingii comb. nov., of Chromatium tepidum to the new genus Thermochromatium as Thermochromatium tepidum comb. nov., of Chromatium salexigens and Chromatium glycolicum to the new genus Halochromatium as Halochromatium salexigens comb. nov. and Halochromatium glycolicum comb. nov., of Chromatium gracile and Chromatium purpuratum to the new genus as Marichromatium gracile comb. nov. and Marichromatium purpuratum comb. nov., of Thiocapsa pfennigii to Thiococcus pfennigii gen. nom. rev., of Thiocapsa halophila to the new genus Thiohalocapsa as Thiohalocapsa halophila comb. nov., and of Chromatium buderi to the new genus Isochromatium as Isochromatium buderi comb. nov.

Chromatiaceae↗

The lysine pathway as a target for a new genera of synthetic antibacterial antibiotics?

Unsaturated analogues of diaminopimelic acid have been synthesized. The amino acids were designed so that they would be reversible or irreversible inhibitors of both of the two last enzymes of the lysine pathway. The compounds were tested with meso-diaminopimelate decarboxylase. trans-3,4-Didehydrodiaminopimelic acid (2) was found to be the most potent inhibitor. The antibacterial activities did not correlate with enzyme inhibiting activities. 4-Methylenediaminopimelic acid 4 showed strong antibacterial properties. It is suggested that L,L-diaminopimelate epimerase could be the target enzyme.

Amino Acid Isomerases↗

Two new genera of the pharyngodonidae (Nematoda: Oxyuroidea) found in rhacophorid frogs of the Ryukyu Archipelago, Japan.

Okinawandros goldbergi n. gen., n. sp. and Ataronema sekii n. gen., n. sp. (Nematoda: Pharyngodonidae) are described from rhacophorid frogs of the Ryukyu Archipelago, Japan. Okinawandros n. gen. resembles Batracholandros Freitas et Ibañez, 1965 and Synodontisia Petter, Vassiliades et Troncy, 1972 but is readily distinguished from the former in lacking laterally situated genital papillae and by having anteriorly directed vagina and from the latter by having operculated eggs and lacking a spicule. Ataronema n. gen. most closely resembles Parathelandros Baylis, 1930 but is readily distinguished because the posterior pair of caudal papillae is not rosette shaped and the eggs are not operculated. Morphological notes of Pharyngodon polypedatis Yamaguti, 1941 are included.

Animals↗