Determination of the Survival of Bacteriophage M13 from Chemical and Physical Challenges to Assist in Its Sustainable Bioprocessing

Steven D. Branston,Emma C. Stanley,John M. Ward,Eli Keshavarz-Moore 한국생물공학회 2013 Biotechnology and Bioprocess Engineering Vol.18 No.3

Bacteriophages are naturally infectious particles that replicate extremely efficiently in their bacterial hosts. Consequently, a facility processing bioproducts from a bacterial strain would be typically expected to focus on avoiding bacteriophage contamination. However, bacteriophages themselves are now showing great promise as a whole new class of industrial agents, such as biologically based nano-materials, delivery vectors and antimicrobials. This therefore raises a new challenge for their large-scale manufacture, potentially in contracted facilities shared with the host organism. The key issue is that knowledge of individual bacteriophage behaviour in the face of physical and chemical challenges is frequently incomplete, complicating decision-making regarding their safe introduction to a facility. This study tackles this issue for the filamentous bacteriophage M13. It was found that experimentation to determine an effective decontamination agent was important:Two of the three tested were ineffective. Virkon was considered to be the disinfectant of choice. Bacteriophage M13 was confirmed to be highly desiccation resistant,exhibiting a half-life of up to 120 days. Conversely, it was completely inactivated by strongly acidic and alkaline conditions and by temperatures above 95oC. By understanding the response of a bacteriophage to these challenges, steps towards their sustainable manufacture can be achieved.

Microwave-driven coherent operation of a semiconductor quantum dot charge qubit.

Kim, Dohun,Ward, D R,Simmons, C B,Gamble, John King,Blume-Kohout, Robin,Nielsen, Erik,Savage, D E,Lagally, M G,Friesen, Mark,Coppersmith, S N,Eriksson, M A Nature Pub. Group 2015 Nature nanotechnology Vol.10 No.3

<P>An intuitive realization of a qubit is an electron charge at two well-defined positions of a double quantum dot. This qubit is simple and has the potential for high-speed operation because of its strong coupling to electric fields. However, charge noise also couples strongly to this qubit, resulting in rapid dephasing at all but one special operating point called the 'sweet spot'. In previous studies d.c. voltage pulses have been used to manipulate semiconductor charge qubits but did not achieve high-fidelity control, because d.c. gating requires excursions away from the sweet spot. Here, by using resonant a.c. microwave driving we achieve fast (greater than gigahertz) and universal single qubit rotations of a semiconductor charge qubit. The Z-axis rotations of the qubit are well protected at the sweet spot, and we demonstrate the same protection for rotations about arbitrary axes in the X-Y plane of the qubit Bloch sphere. We characterize the qubit operation using two tomographic approaches: standard process tomography and gate set tomography. Both methods consistently yield process fidelities greater than 86% with respect to a universal set of unitary single-qubit operations.</P>

The Mechanism of Phloem Loading in Rice (Oryza sativa)

엄준섭,전종성,최상봉,John M. Ward 한국분자세포생물학회 2012 Molecules and cells Vol.33 No.5

Carbohydrates, mainly sucrose, that are synthesized in source organs are transported to sink organs to support growth and development. Phloem loading of sucrose is a crucial step that drives long-distance transport by eleva-ting hydrostatic pressure in the phloem. Three phloem loading strategies have been identified, two active mechanisms, apoplastic loading via sucrose transporters and symplastic polymer trapping, and one passive mechanism. The first two active loading mechanisms require metabolic energy, carbohydrate is loaded into the phloem against a concentration gradient. The passive process, diffusion, involves equilibration of sucrose and other metabolites between cells through plasmodesmata. Many higher plant species including Arabidopsis utilize the active loading mechanisms to increase carbohydrate in the phloem to higher concentrations than that in mesophyll cells. In contrast, recent data revealed that a large number of plants, especially woody species, load sucrose passively by maintaining a high concentration in mesophyll cells. However, it still remains to be determined how the worldwide important cereal crop, rice, loads sucrose into the phloem in source organs. Based on the literature and our results, we propose a potential strategy of phloem loading in rice. Elucidation of the phloem loading mechanism should improve our understanding of rice development and facilitate its manipulation towards the increase of crop productivity.

Impact of Airway Virus in Severe Asthmatic Patients: A Pilot Study

Walsh Laura J,Sullivan Ashley,Ward Christopher,Fanning Liam J,O’Byrne Paul M,MacSharry John A,Murphy Desmond M 대한천식알레르기학회 2023 Allergy, Asthma & Immunology Research Vol.15 No.3

The lungs have their own microbiota which seems to be altered in disease processes such as asthma. Viral infection accounts for many asthma exacerbations. Little is known about the lung virome, and the role that viruses play in non-exacerbating asthmatics. We aimed to assess if detection of virus in bronchoscopy samples of asthmatic patients in a non-exacerbating state influences their asthma control and modulates airway cytokine composition. Patients were recruited from a specialist asthma clinic and underwent bronchoscopy with standardised bronchoalveolar lavage (BAL). Viral analysis was performed; cell differential and cytokine levels were measured. Forty-six samples were obtained of which 10.8% demonstrated evidence of airway virus, and 91.3% of patients in the cohort were classed as severe asthmatics. Oral steroid use was significantly higher in severe asthmatic patients with virus detected, and the forced expiratory volume in one second tended to be lower in the virus-detected group. It was also found that BAL interleukin-13 and tumor necrosis factor-α levels were significantly higher in severe asthmatic patients with virus detected. Our results suggest that in severe asthmatics in a non-exacerbating state, the presence of virus resulted in overall poorer asthma control. The pattern of cytokine elevation seen in asthmatic patients with virus detected may provide insight to the pathophysiology involved.

The mechanism of phloem loading in rice (Oryza sativa)

Eom, Joon-Seob,Choi, Sang-Bong,Ward, John M.,Jeon, Jong-Seong Springer-Verlag 2012 Molecules and cells Vol.33 No.5

Hippocampal morphology and cognitive functions in community-dwelling older people: the Lothian Birth Cohort 1936

Valdé,s Herná,ndez, Maria del Carmen,Cox, Simon R.,Kim, Jaeil,Royle, Natalie A.,Muñ,oz Maniega, Susana,Gow, Alan J.,Anblagan, Devasuda,Bastin, Mark E.,Park, Jinah,Starr, John M.,Ward Elsevier 2017 NEUROBIOLOGY OF AGING Vol.52 No.-

<P>Structural measures of the hippocampus have been linked to a variety of memory processes and also to broader cognitive abilities. Gross volumetry has been widely used, yet the hippocampus has a complex formation, comprising distinct subfields which may be differentially sensitive to the deleterious effects of age, and to different aspects of cognitive performance. However, a comprehensive analysis of multidomain cognitive associations with hippocampal deformations among a large group of cognitively normal older adults is currently lacking. In 654 participants of the Lothian Birth Cohort 1936 (mean age = 72.5, SD = 0.71 years), we examined associations between the morphology of the hippocampus and a variety of memory tests (spatial span, letter-number sequencing, verbal recall, and digit backwards), as well as broader cognitive domains (latent measures of speed, fluid intelligence, and memory). Following correction for age, sex, and vascular risk factors, analysis of memory subtests revealed that only right hippocampal associations in relation to spatial memory survived type 1 error correction in subiculum and in CA1 at the head (<I>β</I> = 0.201, <I>p</I> = 5.843 × 10<SUP>−4</SUP>, outward), and in the ventral tail section of CA1 (<I>β</I> = −0.272, <I>p</I> = 1.347 × 10<SUP>−5</SUP>, inward). With respect to latent measures of cognitive domains, only deformations associated with processing speed survived type 1 error correction in bilateral subiculum (<I>β</I><SUB><I>absolute</I></SUB> ≤ 0.247, <I>p</I> < 1.369 × 10<SUP>−4</SUP>, outward), bilaterally in the ventral tail section of CA1 (<I>β</I><SUB><I>absolute</I></SUB> ≤ 0.242, <I>p</I> < 3.451 × 10<SUP>−6</SUP>, inward), and a cluster at the left anterior-to-dorsal region of the head (<I>β</I> = 0.199, <I>p</I> = 5.220 × 10<SUP>−6</SUP>, outward). Overall, our results indicate that a complex pattern of both inward and outward hippocampal deformations are associated with better processing speed and spatial memory in older age, suggesting that complex shape-based hippocampal analyses may provide valuable information beyond gross volumetry.</P>