scholarly journals Identification of lactobacilli by pheS and rpoA gene sequence analyses

2007 ◽  
Vol 57 (12) ◽  
pp. 2777-2789 ◽  
Author(s):  
Sabri M. Naser ◽  
Peter Dawyndt ◽  
Bart Hoste ◽  
Dirk Gevers ◽  
Katrien Vandemeulebroecke ◽  
...  

The aim of this study was to evaluate the use of the phenylalanyl-tRNA synthase alpha subunit (pheS) and the RNA polymerase alpha subunit (rpoA) partial gene sequences for species identification of members of the genus Lactobacillus. Two hundred and one strains representing the 98 species and 17 subspecies were examined. The pheS gene sequence analysis provided an interspecies gap, which in most cases exceeded 10 % divergence, and an intraspecies variation of up to 3 %. The rpoA gene sequences revealed a somewhat lower resolution, with an interspecies gap normally exceeding 5 % and an intraspecies variation of up to 2 %. The combined use of pheS and rpoA gene sequences offers a reliable identification system for nearly all species of the genus Lactobacillus. The pheS and rpoA gene sequences provide a powerful tool for the detection of potential novel Lactobacillus species and synonymous taxa. In conclusion, the pheS and rpoA gene sequences can be used as alternative genomic markers to 16S rRNA gene sequences and have a higher discriminatory power for reliable identification of species of the genus Lactobacillus.

2006 ◽  
Vol 56 (11) ◽  
pp. 2523-2527 ◽  
Author(s):  
Sabri M. Naser ◽  
Marc Vancanneyt ◽  
Cindy Snauwaert ◽  
Gino Vrancken ◽  
Bart Hoste ◽  
...  

The taxonomic position of six Lactobacillus amylophilus strains isolated from swine waste-corn fermentations was reinvestigated. All strains were included in a multilocus sequence analysis (MLSA) study for species identification of Lactobacillus using the genes encoding the phenylalanyl-tRNA synthase alpha subunit (pheS) and RNA polymerase alpha subunit (rpoA). Partial pheS and rpoA gene sequences showed that strains LMG 11400 and NRRL B-4435 represent a separate lineage that is distantly related to the type strain of L. amylophilus, LMG 6900T, and to three other strains of the species. The MLSA data showed that the two strains LMG 11400 and NRRL B-4435 constituted a distinct cluster, sharing 100 % pheS and rpoA gene sequence similarity. The other reference strains clustered together with the type strain of L. amylophilus, LMG 6900T, and were clearly differentiated from strains LMG 11400 and NRRL B-4435 (80 and 89 % pheS and rpoA gene sequence similarity, respectively). The 16S rRNA gene sequences of the latter two strains are 100 % identical, with the nearest phylogenetic neighbour L. amylophilus LMG 6900T showing only 97.2 % 16S rRNA gene sequence similarity. Further polyphasic taxonomic study based on whole-cell protein fingerprinting, DNA–DNA hybridization and biochemical features demonstrated that the two strains represent a single, novel Lactobacillus species, for which the name Lactobacillus amylotrophicus sp. nov. is proposed. The type strain is LMG 11400T (=NRRL B-4436T=DSM 20534T).


2015 ◽  
Vol 65 (Pt_6) ◽  
pp. 1895-1901 ◽  
Author(s):  
Helena Lucena-Padrós ◽  
Juan M. González ◽  
Belén Caballero-Guerrero ◽  
José Luis Ruiz-Barba ◽  
Antonio Maldonado-Barragán

Three isolates originating from Spanish-style green-olive fermentations in a manufacturing company in the province of Seville, Spain, were taxonomically characterized by a polyphasic approach. This included a phylogenetic analysis based on 16S rRNA gene sequences and multi-locus sequence analysis (MLSA) based on pyrH, recA, rpoA, gyrB and mreB genes. The isolates shared 98.0 % 16S rRNA gene sequence similarity with Vibrio xiamenensis G21T. Phylogenetic analysis based on 16S rRNA gene sequences using the neighbour-joining and maximum-likelihood methods showed that the isolates fell within the genus Vibrio and formed an independent branch close to V. xiamenensis G21T. The maximum-parsimony method grouped the isolates to V. xiamenensis G21T but forming two clearly separated branches. Phylogenetic trees based on individual pyrH, recA, rpoA, gyrB and mreB gene sequences revealed that strain IGJ1.11T formed a clade alone or with V. xiamenensis G21T. Sequence similarities of the pyrH, recA, rpoA, gyrB and mreB genes between strain IGJ1.11T and V. xiamenensis G21T were 86.7, 85.7, 97.3, 87.6 and 84.8 %, respectively. MLSA of concatenated sequences showed that strain IGJ1.11T and V. xiamenensis G21T are two clearly separated species that form a clade, which we named Clade Xiamenensis, that presented 89.7 % concatenated gene sequence similarity, i.e. less than 92 %. The major cellular fatty acids (>5 %) of strain IGJ1.11T were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c), C16 : 0 and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c). Enzymic activity profiles, sugar fermentation patterns and DNA G+C content (52.9 mol%) differentiated the novel strains from the closest related members of the genus Vibrio. The name Vibrio olivae sp. nov. is proposed for the novel species. The type strain is IGJ1.11T ( = CECT 8064T = DSM 25438T).


2005 ◽  
Vol 55 (5) ◽  
pp. 1857-1862 ◽  
Author(s):  
Diva do Carmo Teixeira ◽  
Colette Saillard ◽  
Sandrine Eveillard ◽  
Jean Luc Danet ◽  
Paulo Inácio da Costa ◽  
...  

Symptoms of huanglongbing (HLB) were reported in São Paulo State (SPS), Brazil, in March 2004. In Asia, HLB is caused by ‘Candidatus Liberibacter asiaticus' and in Africa by ‘Candidatus Liberibacter africanus’. Detection of the liberibacters is based on PCR amplification of their 16S rRNA gene with specific primers. Leaves with blotchy mottle symptoms characteristic of HLB were sampled in several farms of SPS and tested for the presence of liberibacters. ‘Ca. L. asiaticus' was detected in a small number of samples but most samples gave negative PCR results. Therefore, a new HLB pathogen was suspected. Evidence for an SPS-HLB bacterium in symptomatic leaves was obtained by PCR amplification with universal primers for prokaryotic 16S rRNA gene sequences. The amplified 16S rRNA gene was cloned and sequenced. Sequence analysis and phylogeny studies showed that the 16S rRNA gene possessed the oligonucleotide signatures and the secondary loop structure characteristic of the α-Proteobacteria, including the liberibacters. The 16S rRNA gene sequence phylogenetic tree showed that the SPS-HLB bacterium clustered within the α-Proteobacteria, the liberibacters being its closest relatives. For these reasons, the SPS-HLB bacterium is considered a member of the genus ‘Ca. Liberibacter’. However, while the 16S rRNA gene sequences of ‘Ca. L. asiaticus' and ‘Ca. L. africanus' had 98·4 % similarity, the 16S rRNA gene sequence of the SPS-HLB liberibacter had only 96·0 % similarity with the 16S rRNA gene sequences of ‘Ca. L. asiaticus' or ‘Ca. L. africanus’. This lower similarity was reflected in the phylogenetic tree, where the SPS-HLB liberibacter did not cluster within the ‘Ca. L asiaticus’/‘Ca. L. africanus group’, but as a separate branch. Within the genus ‘Candidatus Liberibacter’ and for a given species, the 16S/23S intergenic region does not vary greatly. The intergenic regions of three strains of ‘Ca. L. asiaticus’, from India, the People's Republic of China and Japan, were found to have identical or almost identical sequences. In contrast, the intergenic regions of the SPS-HLB liberibacter, ‘Ca. L. asiaticus' and ‘Ca. L. africanus' had quite different sequences, with similarity between 66·0 and 79·5 %. These results confirm that the SPS-HLB liberibacter is a novel species for which the name ‘Candidatus Liberibacter americanus' is proposed. Like the African and the Asian liberibacters, the ‘American’ liberibacter is restricted to the sieve tubes of the citrus host. The liberibacter could also be detected by PCR amplification of the 16S rRNA gene in Diaphorina citri, the psyllid vector of ‘Ca. L. asiaticus’, suggesting that this psyllid is also a vector of ‘Ca. L. americanus' in SPS. ‘Ca. L. americanus' was detected in 216 of 218 symptomatic leaf samples from 47 farms in 35 municipalities, while ‘Ca. L. asiaticus' was detected in only 4 of the 218 samples, indicating that ‘Ca. L. americanus' is the major cause of HLB in SPS.


2011 ◽  
Vol 61 (7) ◽  
pp. 1699-1704 ◽  
Author(s):  
H. Christensen ◽  
A. M. Bojesen ◽  
M. Bisgaard

Strains T138021-75T, Pg19 and Pg20 (taxon 25 of Bisgaard) were isolated from guinea pigs and characterized. Strains T138021-75T and Pg20 showed identical 16S rRNA gene sequences and were distantly related to the published strain P224 with the highest 16S rRNA similarity of 98.6 %. These two strains showed 97.8 % sequence similarity with the type strain and other strains of Mannheimia glucosida and 97.3 % similarity with the type strain of Mannheimia varigena, but <97 % similarity with all other type strains of the genus Mannheimia, including Mannheimia haemolytica (96.9 %). Phylogenetic analysis of rpoB gene sequences showed that strain P224 had a distant position (89.9 % gene sequence similarity) compared with the three other strains (T138021-75T, Pg20 and Pg19), which had identical gene sequences. These three novel strains also shared identical recN gene sequences. Phylogenetic analysis of the recN gene sequences showed a close relationship between the three novel strains and strain P224. The DNA–DNA reassociation value between strain T138021-75T and P224 was 81.6 % and 40.3 % between strain T138021-75T and the type strain of M. glucosida. Based on the DNA–DNA reassociation data, strain T138021-75T belonged to a separate species that was closely related to strain P224. Strain P224 differed from strains T138021-75T, Pg20 and Pg19 in the following phenotypic characteristics: activity of ornithine carboxylase, hydrolysis of glycosides, and acid formation from maltose, dextrin, melibiose and raffinose, as well as reactions for α-galactosidase and β-xylosidase. Whole genome similarity calculations based on recN gene sequences showed that strains T138021-75T and P224 were related at the species level (0.932), whereas 16S rRNA and partial rpoB gene sequence comparisons showed a more divergent position of strain P224 compared with the novel strains, including a different host of isolation. The results showed that the three strains of taxon 25 represent a novel species for which the name Mannheimia caviae sp. nov. is proposed. The type strain, T138021-75T ( = CCUG 59995T = DSM 23207T) was isolated from purulent conjunctivitis in guinea pigs. Previous publications have documented both ubiquinones and demethylmenaquinone to be present in the type strain. The G+C content of the DNA of the type strain has been found to be 41.4 mol% (T m).


2011 ◽  
Vol 61 (2) ◽  
pp. 438-442 ◽  
Author(s):  
Benjamin D. Moser ◽  
Hans-Peter Klenk ◽  
Peter Schumann ◽  
Gabriele Pötter ◽  
Brent A. Lasker ◽  
...  

Members of the genus Nocardia are responsible for cutaneous, pulmonary and disseminated human infections. From 2003 to 2008, four nocardioform strains (W8027, W8681, W9071 and W9241T) were isolated from patients in the state of Florida, USA. Ribosomal gene sequencing analysis suggested that a novel species of the genus Nocardia had been isolated. These strains were subjected to a taxonomic analysis using a polyphasic approach. Phenotypic analyses included morphological examination, biochemical profiling and antimicrobial susceptibility testing. Molecular studies included 16S rRNA and DNA gyrase B subunit (gyrB) gene sequence analyses and DNA–DNA hybridization. Phylogenetic neighbours were determined through 16S rRNA and gyrB gene sequence analyses. Phenotypic characteristics that differentiated the novel isolates from phylogenetically related species were growth at 45 °C, and three of the four novel strains utilized l-rhamnose. The antimicrobial profiles could not reliably distinguish the novel species from related nocardiae. Analysis showed that the 16S rRNA gene sequences of the four novel isolates were identical. The blast analysis of the near full-length 16S rRNA gene showed 99.2 % sequence similarity to Nocardia araoensis DSM 44729T, Nocardia arthritidis DSM 44731T and Nocardia beijingensis JCM 10666T, 98.7 % to Nocardia amamiensis DSM 45066T, 98.2 % to Nocardia pneumoniae JCM 12119T and 97.8 % to Nocardia takedensis JCM 13313T. Analysis of partial gyrB gene sequences showed that the novel isolates had 95.4 % similarity to N. arthritidis DSM 44731T, 95.3 % to Nocardia gamkensis DSM 44956T, 94.4 % to N. pneumoniae JCM 12119T, 93.8 % to Nocardia asiatica DSM 44668T, 93.5 % to N. amamiensis DSM 45066T, 93.4 % to N. beijingensis JCM 10666T and 93.2 % to N. araoensis DSM 44729T. The DNA–DNA relatedness values between the four novel strains were 86–89 %; the relatedness value for strain W9241T compared with N. beijingensis JCM 10666T was 47 % and 46 % with N. araoensis DSM 44729T, 44 % with N. arthritidis DSM 44731T, 32 % with N. amamiensis DSM 45066T and 20 % with N. asiatica DSM 44668T. The results of the taxonomic analysis suggested that the new isolates represent a novel species of the genus Nocardia for which the name Nocardia niwae sp. nov. is proposed. The type strain is W9241T (=DSM 45340T=CCUG 57756T).


Nematology ◽  
2014 ◽  
Vol 16 (7) ◽  
pp. 863-877 ◽  
Author(s):  
Reza Ghaderi ◽  
Akbar Karegar ◽  
Gholamreza Niknam ◽  
Sergei A. Subbotin

Sixteen species,Amplimerlinius globigerus,A. macrurus,Bitylenchus parvus,Merlinius brevidens,M. nanus,Neodolichorhynchus phaseoli,Paramerlinius neohexagrammus,Pratylenchoides alkani,P. ritteri,P. utahensis,Scutylenchus paniculoides,S. rugosus,S. tartuensis,Scutylenchussp. A,Trophurus imparandTylenchorhynchus brassicae, from the families Telotylenchidae and Merliniidae were collected from different locations in Iran and molecularly characterised using sequencing of the D2D3 expansion fragments of the 28S rRNA gene. Morphometrics and light micrography for studied species are also provided as vouchers. The phylogenetic relationships of Telotylenchidae and Merliniidae with other representatives of the order Tylenchida, as obtained from Bayesian inference and Maximum likelihood analysis of partial 28S rRNA gene sequences, are presented and discussed. The results of phylogenetic analysis were in accordance with classifications in whichBitylenchusandScutylenchusare considered as separate genera, butTessellusandTelotylenchuswere synonyms ofTylenchorhynchus. The Shimodaira-Hasegawa test of the 28S rRNA gene sequence alignment and trees rejected a large genus concept ofTylenchorhynchusand the constrained monophyly for Belonolaimidae revealed within this family two genera groups:i) BelonolaimusandIbipora; andii) CarphodorusandMorulaimus. The present results also support the combination ofPratylenchoidesand Merliniinae into a single family, the Merliniidae.


2006 ◽  
Vol 56 (7) ◽  
pp. 1681-1683 ◽  
Author(s):  
Sabri M. Naser ◽  
Marc Vancanneyt ◽  
Bart Hoste ◽  
Cindy Snauwaert ◽  
Jean Swings

The applicability of a multilocus sequence analysis (MLSA)-based identification system for lactobacilli was evaluated. Two housekeeping genes that code for the phenylalanyl-tRNA synthase α-subunit (pheS) and RNA polymerase α-subunit (rpoA) were sequenced and analysed for members of the Lactobacillus salivarius species group. The type strains of Lactobacillus acidipiscis and Lactobacillus cypricasei were investigated further using a third gene that encodes the α-subunit of ATP synthase (atpA). The MLSA data revealed close relatedness between L. acidipiscis and L. cypricasei, with 99.8–100 % pheS, rpoA and atpA gene sequence similarities. Comparison of the 16S rRNA gene sequences of the type strains of the two species confirmed the close relatedness (99.8 % gene sequence similarity) between the two taxa. Similar phenotypes and high DNA–DNA binding values in the range of 84 to 97.5 % confirmed that L. acidipiscis and L. cypricasei are synonymous species. On the basis of the present study, it is proposed that Lactobacillus cypricasei is a later heterotypic synonym of Lactobacillus acidipiscis.


Microbiology ◽  
2005 ◽  
Vol 151 (7) ◽  
pp. 2141-2150 ◽  
Author(s):  
Sabri M. Naser ◽  
Fabiano L. Thompson ◽  
Bart Hoste ◽  
Dirk Gevers ◽  
Peter Dawyndt ◽  
...  

The aim of this study was to evaluate the use of RNA polymerase α subunit (rpoA) and phenylalanyl-tRNA synthase (pheS) gene sequences as species identification tools for enterococci. Ninety-six representative strains comprising all currently recognized Enterococcus species were examined. rpoA gene sequences generated a robust classification into species groups similar to the one based on 16S rRNA gene sequence analysis. On the other hand, the pheS gene is a fast-evolving clock even better suited for species delineation than the rpoA gene, but not for recognition of species groups within Enterococcus as determined by both rpoA and 16S rRNA genes. All enterococcal species were clearly differentiated on the basis of their rpoA and pheS sequences. Evaluation of intraspecies variation showed that both rpoA and pheS genes have a high degree of homogeneity among strains of the same species. Strains of the same enterococcal species have at least 99 % rpoA and 97 % pheS gene sequence similarity, whereas, different enterococcal species have at maximum 97 % rpoA and 86 % pheS gene sequence similarity. It was concluded that both genes can be used as reliable tools for identification of clinical and environmental species of Enterococcus and are efficient screening methods for the detection of novel species. The sequence data obtained in this study were compared to the available atpA and 16S rRNA gene sequences. The MLSA approach to Enterococcus taxonomy provides portable, highly reproducible data with lower costs for rapid identification of all enterococcal species.


2010 ◽  
Vol 60 (12) ◽  
pp. 2697-2704 ◽  
Author(s):  
Byoung Jun Kim ◽  
Hee-Youn Kim ◽  
Yeo-Jun Yun ◽  
Bum-Joon Kim ◽  
Yoon-Hoh Kook

Partial RNA polymerase β-subunit gene (rpoB) sequences (315 bp) were determined and used to differentiate the type strains of 23 species of the genus Bifidobacterium. The sequences were compared with those of the partial hsp60 (604 bp) and 16S rRNA genes (1475 or 1495 bp). The rpoB gene sequences showed nucleotide sequence similarities ranging from 84.1 % to 99.0 %, while the similarities of the hsp60 sequences ranged from 78.5 % to 99.7 % and the 16S rRNA gene sequence similarities ranged from 89.4 % to 99.2 %. The phylogenetic trees constructed from the sequences of these three genes showed similar clustering patterns, with the exception of several species. The Bifidobacterium catenulatum–Bifidobacterium pseudocatenulatum, Bifidobacterium pseudolongum subsp. pseudolongum–Bifidobacterium pseudolongum subsp. globosum and Bifidobacterium gallinarum–Bifidobacterium pullorum–Bifidobacterium saeculare groups were more clearly differentiated in the partial rpoB and hsp60 gene sequence trees than they were in the 16S rRNA gene tree. Based on sequence similarities and tree topologies, the newly determined rpoB gene sequences are suitable molecular markers for the differentiation of species of the genus Bifidobacterium and support various other molecular tools used to determine the relationships among species of this genus.


Sign in / Sign up

Export Citation Format

Share Document