Microbial Populations Responsive to Denitrification-Inducing Conditions in Rice Paddy Soil, as Revealed by Comparative 16S rRNA Gene Analysis

ABSTRACT Rice paddy soil has been shown to have strong denitrifying activity. However, the microbial populations responsible for nitrate respiration and denitrification have not been well characterized. In this study, we performed a clone library analysis of >1,000 clones of the nearly full-length 16S rRNA gene to characterize bacterial community structure in rice paddy soil. We also identified potential key players in nitrate respiration and denitrification by comparing the community structures of soils with strong denitrifying activity to those of soils without denitrifying activity. Clone library analysis showed that bacteria belonging to the phylum Firmicutes, including a unique Symbiobacterium clade, dominated the clones obtained in this study. Using the template match method, several operational taxonomic units (OTUs), most belonging to the orders Burkholderiales and Rhodocyclales, were identified as OTUs that were specifically enriched in the sample with strong denitrifying activity. Almost one-half of these OTUs were classified in the genus Herbaspirillum and appeared >10-fold more frequently in the soils with strong denitrifying activity than in the soils without denitrifying activity. Therefore, OTUs related to Herbaspirillum are potential key players in nitrate respiration and denitrification under the conditions used.

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Croceifilum oryzae gen. nov., sp. nov., isolated from rice paddy soil

INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY ◽

10.1099/ijsem.0.000537 ◽

2015 ◽

Vol 65 (Pt_11) ◽

pp. 4061-4065 ◽

Cited By ~ 15

Author(s):

Kouta Hatayama ◽

Teruaki Kuno

Keyword(s):

Phylogenetic Analysis ◽

16S Rrna ◽

16S Rrna Gene ◽

Paddy Soil ◽

Rice Paddy ◽

Diaminopimelic Acid ◽

Rrna Gene ◽

Gene Sequences ◽

16S Rrna Gene Sequences ◽

Rice Paddy Soil

A mesophilic, aerobic, Gram-stain-positive, filamentous bacterial strain, designated ZYf1a3T, was isolated from rice paddy soil in Japan. This strain grew on a solid medium with formation of substrate mycelium; endospores were produced singly along the mycelium. Formation of aerial mycelium was not observed on any of the media tested. This strain produced a characteristic saffron yellow soluble pigment. Cloned 16S rRNA gene sequences of strain ZYf1a3T yielded three different copies (similarity between the three sequences: 99.8–99.9 %). One of these sequences had one base deletion. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain ZYf1a3T belongs to an independent phylogenetic lineage of the family Thermoactinomycetaceae. The cell wall of strain ZYf1a3T contained meso-diaminopimelic acid, alanine and glutamic acid, but no characteristic sugars. It contained menaquinone 7 as the sole menaquinone. The major cellular fatty acids were iso-C15 : 0 and anteiso-C15 : 0.The major polar lipids were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidyl-N-methylethanolamine and unidentified aminophospholipids. The DNA G+C content was 42.5 mol%. From phylogenetic analysis based on 16S rRNA gene sequences and phenotypic characteristics, this strain is considered to represent a novel species in a new genus, for which the name Croceifilum oryzae gen. nov., sp. nov. is proposed. The type strain of Croceifilum oryzae is ZYf1a3T ( = JCM 30426T = CCUG 66446T = DSM 46876T).

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Diversity and Structure of the Methanogenic Community in Anoxic Rice Paddy Soil Microcosms as Examined by Cultivation and Direct 16S rRNA Gene Sequence Retrieval

Applied and Environmental Microbiology ◽

10.1128/aem.64.3.960-969.1998 ◽

1998 ◽

Vol 64 (3) ◽

pp. 960-969 ◽

Cited By ~ 510

Author(s):

Regine Großkopf ◽

Peter H. Janssen ◽

Werner Liesack

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Paddy Soil ◽

Rice Paddy ◽

16S Rrna Genes ◽

Rrna Genes ◽

Rrna Gene ◽

Rice Paddy Soil ◽

Methanogenic Community ◽

Environmental Sequences

ABSTRACT A dual approach consisting of cultivation and molecular retrieval of partial archaeal 16S rRNA genes was carried out to characterize the diversity and structure of the methanogenic community inhabiting the anoxic bulk soil of flooded rice microcosms. The molecular approach identified four groups of known methanogens. Three environmental sequences clustered with Methanobacterium bryantii andMethanobacterium formicicum, six were closely related but not identical to those of strains of Methanosaeta concilii, two grouped with members of the genus Methanosarcina, and two were related to the methanogenic endosymbiont of Plagiopyla nasuta. The cultivation approach via most-probable-number counts with a subsample of the same soil as an inoculum yielded cell numbers of up to 107 per g of dry soil for the H2-CO2-utilizing methanogens and of up to 106 for the acetate-utilizing methanogens. Strain VeH52, isolated from the terminal positive dilution on H2-CO2, grouped within the phylogenetic radiation characterized by M. bryantii and M. formicicum and the environmental sequences of theMethanobacterium-like group. A consortium of two distinct methanogens grew in the terminal positive culture on acetate. These two organisms showed absolute 16S rRNA gene identities with environmental sequences of the novel Methanosaeta-like group and theMethanobacterium-like group. Methanosarcinaspp. were identified only in the less-dilute levels of the same dilution series on acetate. These data correlate well with acetate concentrations of about 11 μM in the pore water of this rice paddy soil. These concentrations are too low for the growth of knownMethanosarcina spp. but are at the acetate utilization threshold of Methanosaeta spp. Thus, our data indicatedMethanosaeta spp. and Methanobacterium spp. to be the dominant methanogenic groups in the anoxic rice soil, whereasMethanosarcina spp. appeared to be less abundant.

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Molecular Retrieval of Large 16S rRNA Gene Fragments from an Italian Rice Paddy Soil Affiliated with the Class Actinobacteria

Systematic and Applied Microbiology ◽

10.1016/s0723-2020(00)80033-8 ◽

2000 ◽

Vol 23 (4) ◽

pp. 582-584 ◽

Cited By ~ 16

Author(s):

Heiner Lüdemann ◽

Ralf Conrad

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Paddy Soil ◽

Rice Paddy ◽

Rrna Gene ◽

Rice Paddy Soil

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Sandarakinorhabdus rubra sp. nov., and Sandarakinorhabdus oryzae sp. nov., isolated from oxidized rice paddy soil

INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY ◽

10.1099/ijsem.0.004722 ◽

2021 ◽

Author(s):

Geon-Yeong Cho ◽

Kyung-Sook Whang

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Paddy Soil ◽

Type Strain ◽

Type Species ◽

Rice Paddy ◽

Rrna Gene ◽

Rice Paddy Soil ◽

Content Type ◽

Link Type

Three Gram-stain-negative, motile or non-motile, rod-shaped, facultatively aerobic strains, designated MO-4T, NP-34 and NM-18T, were isolated from oxidized rice paddy soil in Chungbuk, Republic of Korea. Colonies were circular and convex with entire margins, red in colour on R2A after 3 days at 30 °C. The three strains grew at pH 5.0–10.0 (optimum, pH 8.0), at 15–45 °C (optimum, 30 °C) and at salinities of 0–1.5 % (w/v) NaCl (optimum, 0.4 % NaCl). The results of phylogenetic analyses based on 16S rRNA gene sequences indicated that the three isolates represent members of the genus Sandarakinorhabdus and strains MO-4T and NP-34 were most closely related to Sandarakinorhabdus cyanobacteriorum TH057T (97.7 %) and Sandarakinorhabdus limnophila DSM 17366T (97.1 %). NM-18T showed highest 16S rRNA gene sequence similarities to Sandarakinorhabdus limnophila DSM 17366T (98.7 %) and Sandarakinorhabdus cyanobacteriorum TH057T (96.7 %). Genomic similarities between strains MO-4T and NM-18T and the two type strains of species of the genus Sandarakinorhabdus based on average nucleotide identity and digital DNA–DNA hybridization values were lower than the species delineation thresholds. The major fatty acids were iso-C18 : 1 ω7c and summed feature 3. The DNA G+C contents of strains MO-4T and NM-18T, obtained from genome sequencing data, were 67.6 and 66.6 mol%, respectively. On the basis of these genotypic and phenotypic characteristics, the three strains are assigned to two novel species of the genus Sandarakinorhabdus , for which the names Sandarakinorhabdus rubra sp. nov. (type strain MO-4T =KACC 21378=NBRC 114106) and Sandarakinorhabdus oryzae sp. nov. (type strain NM-18T=KACC 21379=NBRC 113957) are proposed.

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Human Isolates of Large Colony-Forming β Hemolytic Group G Streptococci form a Distinct Clade upon 16S rRNA Gene Analysis

Streptococci and the Host - Advances in Experimental Medicine and Biology ◽

10.1007/978-1-4899-1825-3_87 ◽

1997 ◽

pp. 363-365 ◽

Cited By ~ 3

Author(s):

Norbert Schnitzler ◽

Gerhard Haase ◽

Andreas Podbielski ◽

Achim Kaufhold ◽

Christoph Lämmler ◽

...

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Gene Analysis ◽

Rrna Gene ◽

16S Rrna Gene Analysis ◽

Group G Streptococci ◽

Large Colony

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Resource Development and Investigation of Novel Species from Unidentified Pathogens in NCCP using MALDI-TOF MS and 16S rRNA Gene Analysis

Journal of Bacteriology and Virology ◽

10.4167/jbv.2016.46.4.201 ◽

2016 ◽

Vol 46 (4) ◽

pp. 201

Author(s):

Won Seon Yu ◽

Kyeong Min Lee ◽

Kyu Jam Hwang

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Novel Species ◽

Resource Development ◽

Gene Analysis ◽

Rrna Gene ◽

16S Rrna Gene Analysis ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Tof Ms

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Clinical Relevance of the Microbiome in Odontogenic Abscesses

Biology ◽

10.3390/biology10090916 ◽

2021 ◽

Vol 10 (9) ◽

pp. 916

Author(s):

Sebastian Böttger ◽

Silke Zechel-Gran ◽

Daniel Schmermund ◽

Philipp Streckbein ◽

Jan-Falco Wilbrand ◽

...

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Oral Microbiome ◽

Molecular Methods ◽

Gene Analysis ◽

Rrna Gene ◽

16S Rrna Gene Analysis ◽

Cultural Methods ◽

Odontogenic Abscess ◽

Polymicrobial Infections

Odontogenic abscesses are usually caused by bacteria of the oral microbiome. However, the diagnostic culture of these bacteria is often prone to errors and sometimes fails completely due to the fastidiousness of the relevant bacterial species. The question arises whether additional pathogen diagnostics using molecular methods provide additional benefits for diagnostics and therapy. Experimental 16S rRNA gene analysis with next-generation sequencing (NGS) and bioinformatics was used to identify the microbiome of the pus in patients with severe odontogenic infections and was compared to the result of standard diagnostic culture. The pus microbiome was determined in 48 hospitalized patients with a severe odontogenic abscess in addition to standard cultural pathogen detection. Cultural detection was possible in 41 (85.42%) of 48 patients, while a pus-microbiome could be determined in all cases. The microbiomes showed polymicrobial infections in 46 (95.83%) cases, while the picture of a mono-infection occurred only twice (4.17%). In most cases, a predominantly anaerobic spectrum with an abundance of bacteria was found in the pus-microbiome, while culture detected mainly Streptococcus, Staphylococcus, and Prevotella spp. The determination of the microbiome of odontogenic abscesses clearly shows a higher number of bacteria and a significantly higher proportion of anaerobes than classical cultural methods. The 16S rRNA gene analysis detects considerably more bacteria than conventional cultural methods, even in culture-negative samples. Molecular methods should be implemented as standards in medical microbiology diagnostics, particularly for the detection of polymicrobial infections with a predominance of anaerobic bacteria.

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