Agrobacterium tumefaciens-mediated plant transformation is the most dominant technique for the transformation of plants. It is used to transform monocotyledonous and dicotyledonous plants. A. tumefaciens apply for stable and transient transformation, random and targeted integration of foreign genes, as well as genome editing of plants. The Advantages of this method include cheapness, uncomplicated operation, high reproducibility, a low copy number of integrated transgenes, and the possibility of transferring larger DNA fragments. Engineered endonucleases such as CRISPR/Cas9 systems, TALENs, and ZFNs can be delivered with this method. Nowadays, Agrobacterium-mediated transformation is used for the Knock in, Knock down, and Knock out of genes. The transformation effectiveness of this method is not always desirable. Researchers applied various strategies to improve the effectiveness of this method. Here, a general overview of the characteristics and mechanism of gene transfer with Agrobacterium is presented. Advantages, updated data on the factors involved in optimizing this method, and other useful materials that lead to maximum exploitation as well as overcoming obstacles of this method are discussed. Moreover, the application of this method in the generation of genetically edited plants is stated. This review can help researchers to establish a rapid and highly effective Agrobacterium-mediated transformation protocol for any plant species.

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OBJECTIVE: to explore the clinical and microbiological characteristics of Rhizobium radiobacter infection, and therefore to provide information for the prevention and treatment of the disease.
METHODS: the clinical and microbiological data were analyzed for patients proved to have Rhizobium radiobacter infection by blood culture obtained from May 2008 to July 2009 in the Second Affiliated Hospital of Fujian Medical University. Related literature were reviewed.
RESULTS: there were 4 males and 2 females aging 5 - 88 years old. All the patients suffered from fever and chillsor malaise, and had increased peripheral WBC or neutrophil count. The majority (5/6) of the infections was pneumonia, characterized by mild cough and expectoration, lung rales, patchy infiltrates on chest X-ray. All the patients had underlying diseases or were immunocompromised. Five of the 6 patients had close soil exposure. Four of the 6 patients received broad-spectrum antibiotics or immunosuppressive therapy. Antibacterial susceptibility testing showed that, all the isolates of Rhizobium radiobacter were susceptible to the third generation cephalosporins, cephamycins, Carbapenems, fluoroquinolones, tetracycline, nitrofurantoin and some of the aminoglycosides, but resistant to penicillins, penicillins/enzyme inhibitors, first and fourth generation cephalosporins, and helices beta-lactamase antibiotics. There were no complications, and all patients recovered uneventfully after treatment with antibiotics according to the susceptibility testing.
CONCLUSIONS: rhizobium radiobacter infections often occur in patients with underlying risk factors. The clinical manifestations of Rhizobium radiobacter infection are nonspecific. The organism is sensitive to most antibiotics, and the clinical outcome is favorable.

Rhizobium radiobacter is an uncommon opportunistic pathogen present in soil. It has been particularly associated with indwelling intravascular devices in immunocompromised patients. In this report, we summarise the case of a patient with multiple myeloma who developed R. radiobacter bacteraemia during autologous stem cell leucopheresis. Retrospective investigation revealed exposure to soil after central venous catheter placement for chemotherapy and leucopheresis access. This is the first reported case of R. radiobacter bacteraemia following probable colonisation of the catheter from soil exposure. We further review the existing literature to delineate prevention and treatment recommendations for line-associated R. radiobacter infections.

The type IV secretion systems (T4SS) are widely distributed among the gram-negative and -positive bacteria. These systems mediate the transfer of DNA and protein substrates across the cell envelope to bacterial or eukaryotic cells generally through a process requiring direct cell-to-cell contact. Bacteria have evolved T4SS for survival during establishment of pathogenic or symbiotic relationships with eukaryotic hosts. The Agrobacterium tumefaciens VirB/D4 T4SS and related conjugation machines serve as models for detailed mechanistic studies aimed at elucidating the nature of translocation signals, machine assembly pathways and architectures, and the dynamics of substrate translocation. The A. tumefaciens VirB/D4 T4SS are polar-localized organelles composed of a secretion channel and an extracellular T pilus. These T4SS are assembled from 11 or more subunits. whose membrane topologies, intersubunit contacts and, in some cases, 3-dimensional structures are known. Recently, powerful in vivo assays have identified C-terminal translocation signals, defined for the first time the translocation route for a DNA substrate through a type IV secretion channel, and supplied evidence that ATP energy consumption contributes to a late stage of machine morphogenesis. Together, these recent findings describe the mechanics of type IV secretion in unprecedented detail.

The tumor-inducing effects of Agrobacterium, Bartonella and Helicobacter bacterial species are compared step by step. An analogy for the existence of these individual steps is considered in connection with the development of cancer. The transformations of eukaryotic cells occur in particular in the type IV secretion system, i.e. involving the simultaneous transmission of DNA and protein from bacterial cells to eukaryotic cells. Thus, transfected cells facilitate the indefinite growth of tissue cells and additionally produce growth factors, triggering further bacterial multiplication. The higher numbers of bacteria then produce more transfection and the cycle repeats as long as the host lives. The main limiting factor is the frequency of bacterial infection, while the secondary rate-limiting factors are the levels of transforming growth factors and factors triggering bacteria growth.
CONCLUSIONS: Analogous processes are probably responsible for the tumor induction by the three different bacterial species; however, the critical points for eradication are different. The early eradication or limitation of B. henselae or H. pylori can prevent hemangiomas, stomach cancer and malignant cell proliferation. The crown gall formation by A. tumefaciens can only be avoided by prevention of the transforming activity of a single bacterial infection. Questions arise as to what is common in the three processes, and the nature of the rate-limiting step in the three different models. The frequency of transformation is the rate-limiting step, but the co-transmission of the DNA-protein complex is common in the three systems.

Agrobacteria are a group of phytopathogenic organisms widely distributed in soil; they are now recognized as rare human pathogens affecting mostly immunocompromised hosts. We report a case of catheter-related bacteremia due to Agrobacterium radiobacter in a neutropenic patient and describe the clinical presentations, treatment strategies and outcome of Agrobacterium infections based on our experience and a literature review. The antimicrobial susceptibility patterns of these organisms appear to be quite variable and collective susceptibility data derived from this and previous reports are provided.