scholarly journals Detection of Toxigenicity by a Probe for the Microcystin Synthetase A Gene (mcyA) of the Cyanobacterial Genus Microcystis: Comparison of Toxicities with 16S rRNA and Phycocyanin Operon (Phycocyanin Intergenic Spacer) Phylogenies

2001 ◽  
Vol 67 (6) ◽  
pp. 2810-2818 ◽  
Author(s):  
Daniel Tillett ◽  
Dorothy L. Parker ◽  
Brett A. Neilan
Keyword(s):  
16S Rrna ◽  
Protein Phosphatase ◽  
Intergenic Spacer ◽  
Rrna Gene ◽  
Monophyletic Cluster ◽  
Microcystin Synthetase ◽  
Field Samples ◽  
Protein Phosphatase Inhibition ◽  
Phosphatase Inhibition ◽  
Cyanobacterial Genus

ABSTRACT The relationship between toxigenicity and phylogeny within the cyanobacterial genus Microcystis is unclear. To investigate this issue, we have designed PCR primers for theN-methyltransferase (NMT) domain of the microcystin synthetase gene mcyA and have probed 37Microcystis sp. cultures as well as several field samples. The NMT region was present in all 18 laboratory strains that gave positive reactions in the protein phosphatase inhibition assay for microcystin but was absent in 17 nontoxic strains. Two other nontoxic strains, one of which had previously been reported to produce microcystin, possessed the NMT region. Detection of NMT-specific DNA in field samples corresponded to periods of toxicity as assessed by protein phosphatase inhibition. The Microcystis strains formed a monophyletic cluster based on 16S rRNA gene sequences but comprised two groups with respect to phycocyanin intergenic spacer (PC-IGS) sequences. Toxic and nontoxic strains appeared to be erratically distributed within the PC-IGS and 16S rRNA trees. Sequence analysis of the NMT domain revealed two coherent groups. The genomic region immediately downstream of the mcyABC cluster in all 20 NMT-positive strains contained an open reading frame of unknown function (uma1) at a conserved distance frommcyC. All nontoxic strains also containeduma1, which is not cotranscribed withmcyABC. The consistent linkage of mcyC touma1 suggests that mcyC has not been frequently transferred into nontoxic strains via any mechanism involving insertion at random chromosomal locations. These results are discussed with respect to various mechanisms that could explain the patchy distribution of toxigenicity among the variousMicrocystis clades.

scholarly journals The Western Progression of Lyme Disease: Infectious and NonclonalBorrelia burgdorferi Sensu LatoPopulations in Grand Forks County, North Dakota

2014 ◽  
Vol 81 (1) ◽  
pp. 48-58 ◽  
Author(s):  
Brandee L. Stone ◽  
Nathan M. Russart ◽  
Robert A. Gaultney ◽  
Angela M. Floden ◽  
Jefferson A. Vaughan ◽  
...  
Keyword(s):  
Lyme Disease ◽  
16S Rrna ◽  
16S Rrna Gene ◽  
North Dakota ◽  
Intergenic Spacer ◽  
Rrna Gene ◽  
Content Type ◽  
Intergenic Spacer Region ◽  
Grand Forks ◽  
The 16S Rrna Gene

ABSTRACTScant attention has been paid to Lyme disease,Borrelia burgdorferi,Ixodes scapularis, or reservoirs in eastern North Dakota despite the fact that it borders high-risk counties in Minnesota. Recent reports ofB. burgdorferiandI. scapularisin North Dakota, however, prompted a more detailed examination. Spirochetes cultured from the hearts of five rodents trapped in Grand Forks County, ND, were identified asB. burgdorferi sensu latothrough sequence analyses of the 16S rRNA gene, the 16S rRNA gene-ileTintergenic spacer region,flaB,ospA,ospC, andp66. OspC typing revealed the presence of groups A, B, E, F, L, and I. Two rodents were concurrently carrying multiple OspC types. Multilocus sequence typing suggested the eastern North Dakota strains are most closely related to those found in neighboring regions of the upper Midwest and Canada. BALB/c mice were infected withB. burgdorferiisolate M3 (OspC group B) by needle inoculation or tick bite. Tibiotarsal joints and ear pinnae were culture positive, andB. burgdorferiM3 was detected by quantitative PCR (qPCR) in the tibiotarsal joints, hearts, and ear pinnae of infected mice. Uninfected larvalI. scapularisticks were able to acquireB. burgdorferiM3 from infected mice; M3 was maintained inI. scapularisduring the molt from larva to nymph; and further, M3 was transmitted from infectedI. scapularisnymphs to naive mice, as evidenced by cultures and qPCR analyses. These results demonstrate that isolate M3 is capable of disseminated infection by both artificial and natural routes of infection. This study confirms the presence of unique (nonclonal) and infectiousB. burgdorferipopulations in eastern North Dakota.

scholarly journals Model-driven discovery of calcium-related protein-phosphatase inhibition in plant guard cell signaling

2019 ◽  
Vol 15 (10) ◽  
pp. e1007429 ◽  
Author(s):  
Parul Maheshwari ◽  
Hao Du ◽  
Jen Sheen ◽  
Sarah M. Assmann ◽  
Reka Albert
Keyword(s):  
Cell Signaling ◽  
Guard Cell ◽  
Protein Phosphatase ◽  
Related Protein ◽  
Model Driven ◽  
Protein Phosphatase Inhibition ◽  
Phosphatase Inhibition

16S rRNA GENE HETEROGENEITY IN THE FILAMENTOUS MARINE CYANOBACTERIAL GENUS LYNGBYA1

2010 ◽  
Vol 46 (3) ◽  
pp. 591-601 ◽  
Author(s):  
Niclas Engene ◽  
R. Cameron Coates ◽  
William H. Gerwick
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Rrna Gene ◽  
Cyanobacterial Genus

Okadaic Acid in New Zealand Sponges: Detection by Cytotoxicity, Protein Phosphatase Inhibition and Immunoassay techniques

1998 ◽  
Vol 11 (4) ◽  
pp. 305-312 ◽  
Author(s):  
Nigel B. Perry ◽  
Gill Ellis ◽  
John W. Blunt ◽  
Timothy A. J. Haystead ◽  
Robin J. Lake ◽  
...  
Keyword(s):  
New Zealand ◽  
Okadaic Acid ◽  
Protein Phosphatase ◽  
Protein Phosphatase Inhibition ◽  
Phosphatase Inhibition

scholarly journals Polynucleobacter cosmopolitanus sp. nov., free-living planktonic bacteria inhabiting freshwater lakes and rivers

2010 ◽  
Vol 60 (1) ◽  
pp. 166-173 ◽  
Author(s):  
Martin W. Hahn ◽  
Elke Lang ◽  
Ulrike Brandt ◽  
Heinrich Lünsdorf ◽  
Qinglong L. Wu ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Novel Species ◽  
Sequence Similarity ◽  
Rrna Gene ◽  
Natural Environments ◽  
The Novel ◽  
Free Living ◽  
Monophyletic Cluster ◽  
Freshwater Habitats

Five heterotrophic, aerobic, catalase- and oxidase-positive, non-motile strains were characterized from freshwater habitats located in Austria, France, Uganda, P. R. China and New Zealand. The strains shared 16S rRNA gene similarities of ≥99.3 %. The novel strains grew on NSY medium over a temperature range of 10–35 °C (two strains also grew at 5 °C and one strain grew at 38 °C) and a NaCl tolerance range of 0.0–0.3 % (four strains grew up to 0.5 % NaCl). The predominant fatty acids were C16 : 0, C18 : 1 ω7c, C12 : 0 3-OH, and summed feature 3 (including C16 : 1 ω7c). The DNA G+C content of strain MWH-MoIso2T was 44.9 mol%. Phylogenetic analysis of 16S rRNA gene sequences demonstrated that the five new strains formed a monophyletic cluster closely related to Polynucleobacter necessarius (96–97 % sequence similarity). This cluster also harboured other isolates as well as environmental sequences which have been obtained from several habitats. Investigations with taxon-specific FISH probes demonstrated that the novel bacteria dwell as free-living, planktonic cells in freshwater systems. Based on the revealed phylogeny and pronounced chemotaxonomic differences to P. necessarius (presence of >7 % C12 : 0 3-OH and absence of C12 : 0 and C12 : 0 2-OH), the new strains are suggested to represent a novel species, for which the name Polynucleobacter cosmopolitanus sp. nov. is proposed. The type strain is MWH-MoIso2T (=DSM 21490T=CIP 109840T=LMG 25212T). The novel species belongs to the minority of described species of free-living bacteria for which both in situ data from their natural environments and culture-based knowledge are available.

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