Kensaku Maejima

Rats receiving nonlethal thermal burns over 20 or 40% of their total body surface area were tested at various intervals for the translocation of indigenous bacteria from their gastrointestinal tracts to their mesenteric lymph nodes, peritoneal cavities, and bloodstreams. No indigenous bacteria were cultured from these organs of control rats or from rats receiving 20% burns. However, 44% of the rats receiving 40% burns exhibited viable Escherichia coli, Proteus mirabilis, Staphylococcus sp. and C

Phytoplasmas are plant pathogenic bacteria associated with devastating damage to over 700 plant species worldwide. It is agriculturally important to identify factors involved in their pathogenicity and to discover effective measures to control phytoplasma diseases. Despite their economic importance, phytoplasmas remain the most poorly characterized plant pathogens, primarily because efforts at in vitro culture, gene delivery, and mutagenesis have been unsuccessful. However, recent molecular stud

Plant pathogens alter the course of plant developmental processes, resulting in abnormal morphology in infected host plants. Phytoplasmas are unique plant-pathogenic bacteria that transform plant floral organs into leaf-like structures and cause the emergence of secondary flowers. These distinctive symptoms have attracted considerable interest for many years. Here, we revealed the molecular mechanisms of the floral symptoms by focusing on a phytoplasma-secreted protein, PHYL1, which induces morp

Flower malformation represented by phyllody is a common symptom of phytoplasma infection induced by a novel family of phytoplasma effectors called phyllogens. Despite the accumulation of functional and structural phyllogen information, the molecular mechanisms of phyllody have not yet been integrated with their evolutionary aspects due to the limited data on their homologs across diverse phytoplasma lineages. Here, we developed a novel universal PCR-based approach to identify 25 phytoplasma phyl

Members of the SEPALLATA (SEP) gene sub-family encode class E floral homeotic MADS-domain transcription factors (MADS TFs) that specify the identity of floral organs. The Arabidopsis thaliana genome contains 4 ancestrally duplicated and functionally redundant SEP genes, SEP1-4. Recently, a gene family of unique effectors, phyllogens, was identified as an inducer of leaf-like floral organs in phytoplasmas (plant pathogenic bacteria). While it was shown that phyllogens target some MADS TFs, includ

For a molecular epidemiological study based on complete genome sequences, 37 Plum pox virus (PPV) isolates were collected from the Kanto region in Japan. Pair-wise analyses revealed that all 37 Japanese isolates belong to the PPV-D strain, with low genetic diversity (less than 0.8%). In phylogenetic analysis of the PPV-D strain based on complete nucleotide sequences, the relationships of the PPV-D strain were reconstructed with high resolution: at the global level, the American, Canadian, and Ja

Plum pox virus (PPV) is one of the most important plant viruses causing serious economic losses. Thus far, strain typing based on the definition of 10 monophyletic strains with partially differentiable biological properties has been the sole approach used for epidemiological characterization of PPV. However, elucidating the genetic determinants underlying intra-strain biological variation among populations or isolates remains a relevant but unexamined aspect of the epidemiology of the virus. In

Phytoplasmas are obligate intracellular plant pathogenic bacteria that can induce phyllody, which is a type of abnormal floral organ development. Phytoplasmas possess phyllogens, which are effector proteins that cause phyllody in plants. Phylogenetic comparisons of <i>phyllogen</i> and 16S rRNA genes have suggested that <i>phyllogen</i> genes undergo horizontal transfer between phytoplasma species and strains. However, the mechanisms and evolutionary implications of this horizontal gene transfer