scholarly journals Identification of Internal Transcribed Spacer Sequence Motifs in Truffles: a First Step toward Their DNA Bar Coding

2007 ◽  
Vol 73 (16) ◽  
pp. 5320-5330 ◽  
Author(s):  
Khalid El Karkouri ◽  
Claude Murat ◽  
Elisa Zampieri ◽  
Paola Bonfante

ABSTRACT This work presents DNA sequence motifs from the internal transcribed spacer (ITS) of the nuclear rRNA repeat unit which are useful for the identification of five European and Asiatic truffles (Tuber magnatum, T. melanosporum, T. indicum, T. aestivum, and T. mesentericum). Truffles are edible mycorrhizal ascomycetes that show similar morphological characteristics but that have distinct organoleptic and economic values. A total of 36 out of 46 ITS1 or ITS2 sequence motifs have allowed an accurate in silico distinction of the five truffles to be made (i.e., by pattern matching and/or BLAST analysis on downloaded GenBank sequences and directly against GenBank databases). The motifs considered the intraspecific genetic variability of each species, including rare haplotypes, and assigned their respective species from either the ascocarps or ectomycorrhizas. The data indicate that short ITS1 or ITS2 motifs (≤50 bp in size) can be considered promising tools for truffle species identification. A dot blot hybridization analysis of T. magnatum and T. melanosporum compared with other close relatives or distant lineages allowed at least one highly specific motif to be identified for each species. These results were confirmed in a blind test which included new field isolates. The current work has provided a reliable new tool for a truffle oligonucleotide bar code and identification in ecological and evolutionary studies.

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Congzhao Fan ◽  
Xiaojin Li ◽  
Jun Zhu ◽  
Jingyuan Song ◽  
Hui Yao

The medicinal plantFerulahas been widely used in Asian medicine, especially in Uyghur medicine in Xinjiang, China. Given that various substitutes and closely related species have similar morphological characteristics,Ferulais difficult to distinguish based on morphology alone, thereby causing confusion and threatening the safe use ofFerula. In this study, internal transcribed spacer 2 (ITS2) sequences were analyzed and assessed for the accurate identification of two salableFerulaspecies (Ferula sinkiangensisandFerula fukangensis) and eight substitutes or closely related species. Results showed that the sequence length of ITS2 ranged from 451 bp to 45 bp, whereas guanine and cytosine contents (GC) were from 53.6% to 56.2%. A total of 77 variation sites were detected, including 63 base mutations and 14 insertion/deletion mutations. The ITS2 sequence correctly identified 100% of the samples at the species level using the basic local alignment search tool 1 and nearest-distance method. Furthermore, neighbor-joining tree successfully identified the genuine plantsF. sinkiangensisandF. fukangensisfrom their succedaneum and closely related species. These results indicated that ITS2 sequence could be used as a valuable barcode to distinguish Uyghur medicineFerulafrom counterfeits and closely related species. This study may broaden DNA barcoding application in the Uyghur medicinal plant field.


Parasitology ◽  
1988 ◽  
Vol 97 (1) ◽  
pp. 63-73 ◽  
Author(s):  
W. C. Gibson ◽  
P. Dukes ◽  
J. K. Gashumba

SUMMARYWe have obtained 5 specific DNA probes for African trypanosomes of the subgenera Trypanozoon and Nannomonas. Each probe consists of one repeat unit of the major repetitive DNA (satellite DNA) of each species or intra-specific group. One probe hybridized with all members of subgenus Trypanozoon (except T. equiperdum which was not tested). In subgenus Nannomonas, one probe recognized T. simiae, but 3 probes were needed to identify all stocks of T. congolense available. Each of the 3 latter probes recognized trypanosomes from one of the 3 major groups of T. congolense previously defined by isoenzyme characterization, i.e. savannah, forest and Kenya coast types. As few as 100 trypanosomes could be unequivocally identified by dot blot hybridization and individual trypanosomes could be identified by in situ hybridization. We show how this simple methodology can be used in the field for the identification of immature and mature trypanosome infections in tsetse.


1991 ◽  
Vol 24 (2) ◽  
pp. 267-272 ◽  
Author(s):  
S. Dubrou ◽  
H. Kopecka ◽  
J. M. Lopez Pila ◽  
J. Maréchal ◽  
J. Prévot

Enteroviruses were specifically detected by dot blot hybridization when using poliovirus type 1 (PV1) derived subgenomic radiolabeled cRNA probes (riboprobes) in environmental water specimens and in the cell cultures in which the viruses were amplificated. The riboprobe corresponding to the 5' noncoding sequence detected the majority of enteroviruses. Hepatitis A virus (HAV) was specifically detected by an HAV cRNA probe corresponding to the 5' noncoding region of its genome. By this test, the limit of detection of coxsackievirus B5 and echovirus 7 seeded in mineral water was 103 to 104 PFU/spot. In cell cultures, positive signals were observed in the lysates of cells infected by one PFU. Higher positive signals were obtained with a short PV1 probe (nt 221-670) corresponding to the 5' noncoding region, which is a well preserved sequence among the enteroviruses, than with PV1 genomic probe. Hybridization allowed a good detection of enteroviral RNAs in wastewater specimens, but with a lower efficiency in surface water. In this case, amplification of viruses in the cell cultures gave significant hybridization results.


2019 ◽  
Vol 19 (4) ◽  
pp. 220-227
Author(s):  
Najmiatul Masykura ◽  
Ummu Habibah ◽  
Siti Fatimah Selasih ◽  
Soegiarto Gani ◽  
Cosphiadi Irawan ◽  
...  

2000 ◽  
Vol 66 (11) ◽  
pp. 4854-4862 ◽  
Author(s):  
Kornelia Smalla ◽  
Holger Heuer ◽  
Antje Götz ◽  
Dagmar Niemeyer ◽  
Ellen Krögerrecklenfort ◽  
...  

ABSTRACT Antibiotic resistance plasmids were exogenously isolated in biparental matings with piggery manure bacteria as plasmid donors inEscherichia coli CV601 and Pseudomonas putidaUWC1 recipients. Surprisingly, IncQ-like plasmids were detected by dot blot hybridization with an IncQ oriV probe in severalP. putida UWC1 transconjugants. The capture of IncQ-like plasmids in biparental matings indicates not only their high prevalence in manure slurries but also the presence of efficiently mobilizing plasmids. In order to elucidate unusual hybridization data (weak or no hybridization with IncQ repB or IncQ oriTprobes) four IncQ-like plasmids (pIE1107, pIE1115, pIE1120, and pIE1130), each representing a different EcoRV restriction pattern, were selected for a more thorough plasmid characterization after transfer into E. coli K-12 strain DH5α by transformation. The characterization of the IncQ-like plasmids revealed an astonishingly high diversity with regard to phenotypic and genotypic properties. Four different multiple antibiotic resistance patterns were found to be conferred by the IncQ-like plasmids. The plasmids could be mobilized by the RP4 derivative pTH10 into Acinetobactersp., Ralstonia eutropha, Agrobacterium tumefaciens, and P. putida, but they showed diverse patterns of stability under nonselective growth conditions in different host backgrounds. Incompatibility testing and PCR analysis clearly revealed at least two different types of IncQ-like plasmids. PCR amplification of total DNA extracted directly from different manure samples and other environments indicated the prevalence of both types of IncQ plasmids in manure, sewage, and farm soil. These findings suggest that IncQ plasmids play an important role in disseminating antibiotic resistance genes.


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
James M. Hodge ◽  
Andrey A. Yurchenko ◽  
Dmitriy A. Karagodin ◽  
Reem A. Masri ◽  
Ryan C. Smith ◽  
...  

Abstract Background The malaria mosquito Anopheles punctipennis, a widely distributed species in North America, is capable of transmitting human malaria and is actively involved in the transmission of the ungulate malaria parasite Plasmodium odocoilei. However, molecular diagnostic tools based on Internal Transcribed Spacer 2 (ITS2) of ribosomal DNA are lacking for this species. Anopheles punctipennis is a former member of the Anopheles maculipennis complex but its systematic position remains unclear. Methods In this study, ITS2 sequences were obtained from 276 An. punctipennis specimens collected in the eastern and midwestern United States and a simple and robust Restriction Fragment Length Polymorphism approach for species identification was developed. The maximum-likelihood phylogenetic tree was constructed based on ITS2 sequences available through this study and from GenBank for 20 species of Anopheles. Results The analysis demonstrated a consistent ITS2 sequence length and showed no indications of intragenomic variation among the samples based on ITS2, suggesting that An. punctipennis represents a single species in the studied geographic locations. In this study, An. punctipennis was found in urban, rural, and forest settings, suggesting its potential broad role in pathogen transmission. Phylogeny based on ITS2 sequence comparison demonstrated the close relationship of this species with other members of the Maculipennis group. Conclusions This study developed molecular tools based on ITS2 sequences for the malaria vector An. punctipennis and clarified the phylogenetic position of the species within the Maculipennis group.


Plant Disease ◽  
2021 ◽  
pp. PDIS-06-20-1290
Author(s):  
Juliana S. Baggio ◽  
Bruna B. Forcelini ◽  
Nan-Yi Wang ◽  
Rafaela G. Ruschel ◽  
James C. Mertely ◽  
...  

Pestalotiopsis-like species have been reported affecting strawberry worldwide. Recently, severe and unprecedented outbreaks have been reported in Florida commercial fields where leaf, fruit, petiole, crown, and root symptoms were observed, and yield was severely affected. The taxonomic status of the fungus is confusing because it has gone through multiple reclassifications over the years. Morphological characteristics, phylogenetic analyses, and pathogenicity tests were evaluated for strawberry isolates recovered from diseased plants in Florida. Phylogenetic analyses derived from the combined internal transcribed spacer, β-tub, and tef1 regions demonstrated that although there was low genetic diversity among the strawberry isolates, there was a clear separation of the isolates in two groups. The first group included isolates recovered over a period of several years, which was identified as Neopestalotiopsis rosae. Most isolates recovered during the recent outbreaks were genetically different and may belong to a new species. On potato dextrose agar, both groups produced white, circular, and cottony colonies. From the bottom, colonies were white to pale yellow for Neopestalotiopsis sp. and pale luteous to orange for N. rosae. Spores for both groups were five-celled with three median versicolored cells. Mycelial growth and spore production were higher for the new Neopestalotiopsis sp. isolates. Isolates from both groups were pathogenic to strawberry roots and crowns. However, the new Neopestalotiopsis sp. proved more aggressive in fruit and leaf inoculation tests, confirming observations from the recent outbreaks in commercial strawberry fields in Florida.


1994 ◽  
Vol 12 (1) ◽  
pp. 107-118 ◽  
Author(s):  
A Van Bael ◽  
R Huygen ◽  
B Himpens ◽  
C Denef

ABSTRACT We have studied the effect of LHRH and neuropeptide Y (NPY) on prolactin (PRL) mRNA levels in pituitary reaggregate cell cultures from 14-day-old female rats, by means of in situ hybridization and Northern blot analysis. As estimated by computer-image analysis, addition of LHRH on day 5 in culture for 40 h resulted in a 37% increase in the total cytoplasmic areas of cells containing PRL mRNA, visualized using a digoxigenin-labelled PRL cRNA. The size of individual PRL-expressing cells was not influenced, nor was the content of PRL mRNA per cell. A similar effect of LHRH was found by dot blot hybridization of extracted RNA. PRL mRNA levels were not affected by NPY. LHRH induced a 29% increase in the number of PRL mRNA-expressing cells processing through the S phase of the cell cycle, visualized by the incorporation of [3H]thymidine ([3H]T) into DNA over 16 h. The fraction of [3H]T-labelled cells was 10–12% of the total cell population. NPY did not influence the number of [3H]T-positive cells expressing PRL mRNA, but completely blocked the effect of LHRH on the latter population. The present data suggest that LHRH, probably via a paracrine action of gonadotrophs, stimulates the recruitment of new lactotrophs, an action which is negatively modulated by NPY. Since the magnitude of this effect was the same in the total pituitary cell population as in cells processing through the S phase of the cell cycle and presumably mitosis, recruitment of lactotrophs seems to be based on differentiation of progenitor or immature cells into PRL-expressing cells, rather than on a mitogenic action on pre-existing lactotrophs alone.


Phytotaxa ◽  
2015 ◽  
Vol 197 (4) ◽  
pp. 267-281 ◽  
Author(s):  
Qian Chen ◽  
KE ZHANG ◽  
GUOZHEN ZHANG ◽  
LEI CAI

Phoma odoratissimi sp. nov. on Viburnum odoratissimum and Syringa oblate, and Phoma segeticola sp. nov. on Cirsium segetum from China are introduced and described, employing a polyphasic approach characterising morphological characteristics, host association and phylogeny. Both species are the first records of Phoma species on their respective hosts. Multi-locus phylogenetic tree was inferred using combined sequences of the internal transcribed spacer regions 1 & 2 and 5.8S nrDNA (ITS), and partial large subunit 28S nrDNA region (LSU), β-tubulin (TUB) region and RNA polymerase II (RPB2) region. The two new species clustered in two separate and distinct lineages, and are distinct from their allied species.


1993 ◽  
Vol 4 (3) ◽  
pp. 159-164 ◽  
Author(s):  
A J Borg ◽  
G Medley ◽  
S M Garland

A total of 377 women, consecutively selected as first attenders to a sexually transmitted diseases clinic in Melbourne, Australia, were examined for overt Condylomata acuminata and were screened for genital HPV DNA types 6, 11, 16, 18, 31, 33 and (35) using 2 dot blot hybridization methods. Overall, there was a 90% positivity correlation between the 2 methods with HPV DNA being detected in 12% of ectocervical samples. Overt warts were found in 15% of the women and HPV DNA was detected at the cervix in 35% with cytology predicting HPV with or without dysplasia in 27%. Thirteen percent had a past history of warts but none on examination and HPV DNA was evident in 16% while 18% had cytological features of HPV. Those with no warts evident and no past history of warts had both HPV DNA and cytological features of HPV in 7%.


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