Mycena, a symbiont of Gastrodia elata, promotes seed germination of G. elata and plays a crucial role in the sexual reproduction of G. elata. However, the lack of genetic transformation system of Mycena blocks the research on the interaction mechanism of the two. In order to establish the protoplast transformation system of Mycena, this study analyzed the protoplast enzymatic hydrolysis system, screened the resistance markers and regeneration medium, and explored the transient transformation. After hydrolysis of Mycena hyphae with complexes enzymes for 8 h and centrifugation at 4 000 r·min~(-1), high-concentration and quality protoplast was obtained. The optimum regeneration medium for Mycena was RMV, and the optimum resistance marker was 50 mg·mL~(-1) hygromycin. The pLH-HygB-HuSHXG-GFP-HdSHXG was transformed into the protoplast of Mycena which then expressed GFP. The established protoplast transformation system of Mycena laid a foundation for analyzing the functional genes of Mycena and the molecular mechanism of the symbiosis of Mycena and G. elata.
Agaricales ; Gastrodia/genetics* ; Protoplasts ; Symbiosis/genetics* ; Transformation, Genetic

We isolated 30 Trichomonas vaginalis for the PCR detection from the gynecological outpatients in the Affiliated Hospital of Zhengzhou University using the specific 16s rDNA primers of Mycoplasma hominis. The results showed that there were 25 cases of Mycoplasma hominis infection, with the infection rate of 83.33%. This gave a clew that the symbiosis of Trichomonas vaginalis with Mycoplasma hominis may be of certain generality in China. We sequenced the ferredoxin gene of 10 Trichomonas vaginalis where 5 Mycoplasma hominis were positive and five negative, and found that the ferredoxin (Fd) gene of the 10 Trichomonas vaginalis were exactly the same. But compared to the genes in the GenBank, a comparative analysis of the gene revealed that there were 3 more ctg bases at the 200th position of encoding leucine, but this did not lead to changes in reading frame. The gene homology was 99%.
Amino Acid Sequence ; Base Sequence ; Female ; Ferredoxins ; genetics ; Humans ; Molecular Sequence Data ; Mycoplasma hominis ; genetics ; physiology ; Symbiosis ; genetics ; Trichomonas vaginalis ; genetics ; physiology

S-Adenosyl-L-methionine decarboxylase (SAMDC) is a key enzyme in the polyamines biosynthesis, thus is essential for basic physiological and biochemical processes in plant. In the present study, a full length cDNA of DoSAMDC1 gene was obtained from symbiotic germinated seeds of an endangered medicinal orchid species Dendrobium officinale, using the rapid amplification of cDNA ends (RACE)-PCR technique for the first time. The full length cDNA was 1 979 bp, with three open reading frames, i.e. tiny-uORF, small-uORF and main ORF (mORF). The mORF was deduced to encode a 368 amino acid (aa) protein with a molecular mass of 40.7 kD and a theoretical isoelectric point of 5.2. The deduced DoSAMDC1 protein, without signal peptide, had two highly conserved function domains (proenzyme cleavage site and PEST domain) and a 22-aa transmembrane domain (89-110). Multiple sequence alignments and phylogenetic relationship analyses revealed DoSAMDC1 had a higher level of sequence similarity to monocot SAMDCs than those of dicot. Expression patterns using qRT-PCR analyses showed that DoSAMDC1 transcripts were expressed constitutively without significant change in the five tissues (not infected with fungi). While in the symbiotic germinated seeds, the expression level was enhanced by 2.74 fold over that in the none-germinated seeds, indicating possible involvement of the gene in symbiotic seed germination of D. officinale.
Adenosylmethionine Decarboxylase ; genetics ; isolation & purification ; Amino Acid Sequence ; Basidiomycota ; physiology ; Cloning, Molecular ; DNA, Complementary ; genetics ; Dendrobium ; enzymology ; genetics ; microbiology ; Germination ; Open Reading Frames ; Phylogeny ; Plants, Medicinal ; enzymology ; genetics ; microbiology ; Seeds ; genetics ; growth & development ; microbiology ; Sequence Alignment ; Symbiosis ; physiology

Recent in vitro studies have revealed that a certain Mycobacterium can survive and multiply within freeliving amoebae. It is believed that protozoans function as host cells for the intracellular replication and evasion of Mycobacterium spp. under harmful conditions. In this study, we describe the isolation and characterization of a bacterium naturally observed within an amoeba isolate acquired from a contact lens storage case. The bacterium multiplied within Acanthamoeba, but exerted no cytopathic effects on the amoeba during a 6-year amoebic culture. Trasnmission electron microscopy showed that the bacteria were randomly distributed within the cytoplasm of trophozoites and cysts of Acanthamoeba. On the basis of the results of 18S rRNA gene analysis, the amoeba was identified as A. lugdunensis. A 16S rRNA gene analysis placed this bacterium within the genus Mycobacterium. The bacterium evidenced positive reactivity for acid-fast and fluorescent acid-fast stains. The bacterium was capable of growth on the Middlebrook 7H11-Mycobacterium-specific agar. The identification and characterization of bacterial endosymbionts of free-living protozoa bears significant implications for our understanding of the ecology and the identification of other atypical mycobacterial pathogens.
Acanthamoeba/genetics/isolation & purification/*microbiology ; Animals ; Base Sequence ; Contact Lens Solutions ; *Contact Lenses ; DNA, Mitochondrial/genetics ; Microscopy, Electron, Transmission/methods ; Mycobacterium/genetics/*isolation & purification ; Phylogeny ; Polymorphism, Restriction Fragment Length ; RNA, Ribosomal, 16S/genetics ; RNA, Ribosomal, 18S/genetics ; Symbiosis

The endosymbionts of 4 strains of Acanthamoeba (KA/E9, KA/E21, KA/E22, and KA/E23) isolated from the infected corneas of Korean patients were characterized via orcein stain, transmission electron microscopic examination, and 16S rDNA sequence analysis. Double membrane-bound, rod-shaped endosymbionts were distributed randomly throughout both the trophozoites and cysts of each of Acanthamoeba isolates. The endosymbionts of KA/E9, KA/E22, and KA/E23 were surrounded by electron-translucent areas. No lacunae-like structures were observed in the endosymbionts of KA/E21, the bacterial cell walls of which were studded with host ribosomes. Comparative analyses of the 16S rDNA sequences showed that the endosymbionts of KA/E9, KA/E22 and KA/E23 were closely related to Caedibacter caryophilus, whereas the KA/E21 endosymbiont was assigned to the Cytophaga-Flavobacterium-Bacteroides (CFB) phylum. In the 4 strains of Acanthamoeba, the hosts of the endosymbionts were identified as belonging to the Acanthamoeba castellanii complex, which corresponds to the T4 genotype. Acanthamoeba KA/E21 evidenced characteristics almost identical to those of KA/E6, with the exception of the existence of endosymbionts. The discovery of these endosymbionts from Acanthamoeba may prove essential to future studies focusing on interactions between the endosymbionts and the amoebic hosts.
Acanthamoeba/genetics/isolation & purification/*microbiology ; Acanthamoeba Keratitis/*microbiology/*parasitology ; Animals ; Bacteria/*genetics/isolation & purification ; Base Sequence ; Cornea/microbiology/*parasitology ; DNA, Mitochondrial/genetics ; Humans ; Korea ; Microscopy, Electron, Transmission/methods ; Oxazines/metabolism ; Phylogeny ; RNA, Ribosomal, 16S/genetics ; RNA, Ribosomal, 18S/genetics ; Symbiosis

Most plants can form a symbiosis in root with microorganisms for mutual benefit, Nonlegumes mainly form the symbiotic mycorrhiza with arbuscular fungi. The interaction is initiated by invasion of arbuscular mycorrhizal (AM) fungi into the plant root, and follows by production of several special signal molecules, such as the symbiosis receptor-like kinase (SYMRK) from plant. SYMRK has an extracellular domain comprising three leucine-rich repeats (LRRs), a transmembrane domain and an cytoplasmic protein kinase domain. Symrk is required for a symbiotic signal transduction pathway from the perception of microbial signal molecules to the rapid symbiosis-related gene activation. Study of symrk may set up a solid foundation for giving further insight on the function and mechanism of plant-fungi symbiosis.
Amino Acid Sequence ; Host-Pathogen Interactions ; Lycopersicon esculentum ; Molecular Sequence Data ; Mycorrhizae ; physiology ; Phosphotransferases ; classification ; genetics ; Phylogeny ; Plant Proteins ; classification ; genetics ; Plant Roots ; enzymology ; genetics ; microbiology ; Sequence Homology, Amino Acid ; Signal Transduction ; genetics ; Symbiosis ; genetics

The mitogen-activated protein kinase (MAPK) cascade, composed of MAPK kinase kinase (MAP3K), MAPK kinase (MAP2K), and MAPK, is abundantly conserved in all eukaryotes. MAPK along with MAPK cascade plays a vital regulatory role in the plant-arbuscular mycorrhiza/rhizobium nodule symbioses. However, the biological function of MAPK in orchid mycorrhiza (OM) symbiosis remains elusive. In the present study, a MAPK gene, designated as DoMPK1 (GenBank accession No. JX297594), was identified from D. officinale roots infected by an OM fungus-Mycena sp. using the reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) methods. The full length cDNA of DoMPK1 was 1 263 bp and encoded a 372 aa protein with a molecular weight of 42.61 kD and an isoelectric point (pI) of 6.07. The deduced DoMPK1 protein contained the conserved serine/threonine-protein kinase catalytic domain (39-325) and MAP kinase signature (77-177). Multiple sequence alignment and phylogenetic analysis demonstrated that DoMPK1 was highly homologous (71%-85%) to MAPK genes from various plant species and was closely related to those from monocots. Real time quantitative PCR (qPCR) analysis revealed that DoMPK1 was constitutively expressed in leaves, stems, roots and seeds, and the transcript abundance was not significantly different in the four included tissues. Furthermore, DoMPK1 transcript was markedly induced in roots at 30 d after fungal infection, with 7.91 fold compared to that of the mock inoculated roots, suggesting implication of DoMPK1 in the early D. officinale and Mycena sp. interaction and an essential role in the symbiosis. Our study characterized a MAPK gene associated with OM symbiosis for the first time, and will be helpful for further functional elucidation of DoMPK1 involving in D. officinale and Mycena sp. symbiotic interaction.
Agaricales ; growth & development ; Amino Acid Sequence ; Base Sequence ; Cloning, Molecular ; DNA, Complementary ; genetics ; Dendrobium ; enzymology ; genetics ; microbiology ; Gene Expression Regulation, Plant ; Mitogen-Activated Protein Kinases ; genetics ; metabolism ; Molecular Weight ; Phylogeny ; Plants, Medicinal ; enzymology ; genetics ; microbiology ; Sequence Alignment ; Symbiosis

Calcium-dependent protein kinases (CDPKs) play an important regulatory role in the plantarbuscular mycorrhiza/rhizobium nodule symbiosis. However, the biological action of CDPKs in orchid mycorrhiza (OM) symbiosis remains unclear. In the present study, a CDPK encoding gene, designated as DoCPK1 (GenBank accession No. JX193703), was identified from D. officinale roots infected by an OM fungus-Mycena sp. using the reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) methods, for the first time. The full length cDNA of DoCPK1 was 2137 bp in length and encoded a 534 aa protein with a molecular weight of 59.61 kD and an isoelectric point (pI) of 6.03. The deduced DoCPK1 protein contained the conserved serine/threonine-protein kinase catalytic domain and four Ca2+ binding EF hand motifs. Multiple sequence alignment demonstrated that DoCPK1 was highly homologous (85%) to the Panax ginseng PgCPK1 (ACY78680), followed by CDPKs genes from wheat, rice, and Arabidopsis (ABD98803, ADM14342, Q9ZSA2, respectively). Phylogenetic analysis showed that DoCPK1 was closely related to CDPKs genes from monocots, such as wheat, maize and rice. Real time quantitative PCR (qPCR) analysis revealed that DoCPK1 was constitutively expressed in the included tissues and the transcript levels were in the order of roots > stems > seeds > leaves. Furthermore, DoCPK1 transcripts were significantly accumulated in roots 30 d after fungal infection, with 5.16 fold compared to that of the mock roots, indicating involvement of DoCPK1 during the early interaction between D. officinale and Mycena sp., and a possible role in the symbiosis process. This study firstly provided important clues of a CDPK gene associated with OM symbiosis, and will be useful for further functional determination of the gene involving in D. officinale and Mycena sp. symbiosis.
Agaricales ; growth & development ; physiology ; Amino Acid Sequence ; Base Sequence ; Cloning, Molecular ; DNA, Complementary ; genetics ; Dendrobium ; enzymology ; genetics ; microbiology ; Gene Expression Regulation, Plant ; Molecular Weight ; Mycorrhizae ; growth & development ; physiology ; Phylogeny ; Plant Leaves ; enzymology ; genetics ; microbiology ; Plant Roots ; enzymology ; genetics ; microbiology ; Plant Stems ; enzymology ; genetics ; microbiology ; Plants, Medicinal ; enzymology ; genetics ; microbiology ; Protein Kinases ; genetics ; metabolism ; Seeds ; enzymology ; genetics ; microbiology ; Sequence Alignment ; Symbiosis

In a previous study, we reported our discovery of Acanthamoeba contamination in domestic tap water; in that study, we determined that some Acanthamoeba strains harbor endosymbiotic bacteria, via our molecular characterization by mitochondrial DNA restriction fragment length polymorphism (Mt DNA RFLP). Five (29.4%) among 17 Acanthamoeba isolates contained endosymbionts in their cytoplasm, as demonstrated via orcein staining. In order to estimate their pathogenicity, we conducted a genetic characterization of the endosymbionts in Acanthamoeba isolated from domestic tap water via 16S rDNA sequencing. The endosymbionts of Acanthamoeba sp. KA/WP3 and KA/WP4 evidenced the highest level of similarity, at 97% of the recently published 16S rDNA sequence of the bacterium, Candidatus Amoebophilus asiaticus. The endosymbionts of Acanthamoeba sp. KA/WP8 and KA/WP12 shared a 97% sequence similarity with each other, and were also highly similar to Candidatus Odyssella thessalonicensis, a member of the alpha-proteobacteria. The endosymbiont of Acanthamoeba sp. KA/WP9 exhibits a high degree of similarity (85-95%) with genus Methylophilus, which is not yet known to harbor any endosymbionts. This is the first report, to the best of our knowledge, to show that Methylophilus spp. can live in the cytoplasm of Acanthamoeba.
Acanthamoeba/isolation & purification/*microbiology/ultrastructure ; Alphaproteobacteria/classification/genetics/*isolation & purification ; Animals ; Bacteroidetes/classification/genetics/*isolation & purification ; Cluster Analysis ; DNA, Bacterial/chemistry/genetics ; DNA, Ribosomal/chemistry/genetics ; Fresh Water/*parasitology ; Korea ; Methylophilus/classification/genetics/*isolation & purification ; Microscopy, Electron, Transmission ; Phylogeny ; RNA, Ribosomal, 16S/genetics ; Sequence Analysis, DNA ; *Symbiosis