scholarly journals Biosensor-Based Directed Evolution of Methanol Dehydrogenase from Lysinibacillus xylanilyticus

2021 ◽  
Vol 22 (3) ◽  
pp. 1471
Author(s):  
Thien-Kim Le ◽  
Su-Bin Ju ◽  
Hye-Won Lee ◽  
Jin-Young Lee ◽  
So-Hyung Oh ◽  
...  
Keyword(s):  
Cell Sorting ◽  
Turnover Rate ◽  
Methanol Conversion ◽  
Transcriptional Factor ◽  
Methanol Dehydrogenase ◽  
Mutant Library ◽  
Wild Type ◽  
High Turnover ◽  
Catalytic Activities ◽  
Km Value

Methanol dehydrogenase (Mdh), is a crucial enzyme for utilizing methane and methanol as carbon and energy sources in methylotrophy and synthetic methylotrophy. Engineering of Mdh, especially NAD-dependent Mdh, has thus been actively investigated to enhance methanol conversion. However, its poor catalytic activity and low methanol affinity limit its wider application. In this study, we applied a transcriptional factor-based biosensor for the direct evolution of Mdh from Lysinibacillus xylanilyticus (Lxmdh), which has a relatively high turnover rate and low KM value compared to other wild-type NAD-dependent Mdhs. A random mutant library of Lxmdh was constructed in Escherichia coli and was screened using formaldehyde-detectable biosensors by incubation with low methanol concentrations. Positive clones showing higher fluorescence were selected by fluorescence-activated cell sorting (FACS) system, and their catalytic activities toward methanol were evaluated. The successfully isolated mutants E396V, K318N, and K46E showed high activity, particularly at very low methanol concentrations. In kinetic analysis, mutant E396V, K318N, and K46E had superior methanol conversion efficiency, with 79-, 23-, and 3-fold improvements compared to the wild-type, respectively. These mutant enzymes could thus be useful for engineering synthetic methylotrophy and for enhancing methanol conversion to various useful products.

scholarly journals In vivo dynamics of skeletal muscle Dystrophin in zebrafish embryos revealed by improved FRAP analysis

eLife ◽  
2015 ◽  
Vol 4 ◽  
Author(s):  
Fernanda Bajanca ◽  
Vinicio Gonzalez-Perez ◽  
Sean J Gillespie ◽  
Cyriaque Beley ◽  
Luis Garcia ◽  
...  
Keyword(s):  
Turnover Rate ◽  
Zebrafish Embryos ◽  
Wild Type ◽  
High Turnover ◽  
Complex Protein ◽  
In Vivo Analysis ◽  
Membrane Bound ◽  
First Time ◽  
Developing Muscle

Dystrophin forms an essential link between sarcolemma and cytoskeleton, perturbation of which causes muscular dystrophy. We analysed Dystrophin binding dynamics in vivo for the first time. Within maturing fibres of host zebrafish embryos, our analysis reveals a pool of diffusible Dystrophin and complexes bound at the fibre membrane. Combining modelling, an improved FRAP methodology and direct semi-quantitative analysis of bleaching suggests the existence of two membrane-bound Dystrophin populations with widely differing bound lifetimes: a stable, tightly bound pool, and a dynamic bound pool with high turnover rate that exchanges with the cytoplasmic pool. The three populations were found consistently in human and zebrafish Dystrophins overexpressed in wild-type or dmdta222a/ta222a zebrafish embryos, which lack Dystrophin, and in Gt(dmd-Citrine)ct90a that express endogenously-driven tagged zebrafish Dystrophin. These results lead to a new model for Dystrophin membrane association in developing muscle, and highlight our methodology as a valuable strategy for in vivo analysis of complex protein dynamics.

scholarly journals Probing the Role of Sigma π Interaction and Energetics in the Catalytic Efficiency of Endo-1,4-β-Xylanase

2012 ◽  
Vol 78 (24) ◽  
pp. 8817-8821 ◽  
Author(s):  
Raushan Kumar Singh ◽  
Manish Kumar Tiwari ◽  
In-Won Kim ◽  
Zhilei Chen ◽  
Jung-Kul Lee
Keyword(s):  
Amino Acid ◽  
Turnover Rate ◽  
Catalytic Efficiency ◽  
Binding Pocket ◽  
Wild Type ◽  
High Turnover ◽  
Substrate Binding Pocket ◽  
Content Type ◽  
Important Residue

ABSTRACTChaetomium globosumendo-1,4-β-xylanase (XylCg) is distinguished from other xylanases by its high turnover rate (1,860 s−1), the highest ever reported for fungal xylanases. One conserved amino acid, W48, in the substrate binding pocket of wild-type XylCg was identified as an important residue affecting XylCg's catalytic efficiency.

FAKTOR PERSONAL YANG BERHUBUNGAN DENGAN KOMITMEN ORGANISASI PERAWAT RSUD EMBUNG FATIMAH BATAM

2020 ◽  
Vol 5 (3) ◽  
pp. 875
Author(s):  
Asfri Sri Rahmadeni
Keyword(s):  
Organizational Commitment ◽  
Turnover Rate ◽  
Sampling Technique ◽  
Hospital Nurses ◽  
Test Results ◽  
Personal Factors ◽  
High Turnover ◽  
Chi Square ◽  
Cross Sectional ◽  
Chi Square Test

<p class="Normal1"><em>Commitment is the attitude or behavior of likes or dislikes shown by someone against the organization at work. Indonesia is recorded as a nurse who has a low organizational commitment (76%) so it harms services. This phenomenon in the hospital can be seen from the indicator of the high turnover rate of nurses which reaches 30.9% which exceeds the standard &lt;5%. Many factors affect organizational commitment. The purpose of this study was to analyze the Personal Factors Associated with Organizational Commitment of Hospital Nurses. This study is a cross-sectional analytic study and purposive sampling technique with a sample of 59 nurses. Chi-Square test results obtained personal factors that have a relationship with organizational commitment Nurse Hospital is age with p = 0,000 and education with p = 0,000, personal factors not related to organizational commitment are gender p = 1,053 and years of service with p = 1,147. Hospitals should conduct research/surveys on Organizational Commitment periodically as an evaluation material in the context of the organization's development and development in the future</em>.</p>

scholarly journals Consultant staffing in UK congenital cardiac services: a 10-year survey of leavers and joiners

Open Heart ◽  
2021 ◽  
Vol 8 (2) ◽  
pp. e001723
Author(s):  
David Steven Crossland ◽  
Richard Ferguson ◽  
Alan Magee ◽  
Petra Jenkins ◽  
Frances A Bulock ◽  
...  
Keyword(s):  
Turnover Rate ◽  
Adult Congenital Heart Disease ◽  
Staff Retention ◽  
High Turnover ◽  
National Review ◽  
Adult Congenital ◽  
Level 1 ◽  
The Uk ◽  
Cardiac Surgeons ◽  
Work Abroad

ObjectivesTo report the numbers of consultant congenital cardiac surgeons and cardiologists who have joined and left UK practice over the last 10 years and explore the reasons for leaving.MethodsRetrospective observational questionnaire study completed between 11 June 2019 and 1 July 2020 by UK level 1 congenital cardiac centres of 10-year consultant staff movement and reasons suggested for leaving UK practice.ResultsAt survey completion there were 218 (202 whole time equivalent (WTE)) consultant cardiologists and surgeons working within level 1 centres made up of 39 (38 WTE) surgeons, 137 (128.5 WTE) paediatric cardiologists, 42 (35.5 WTE) adult congenital heart disease (ACHD) cardiologists. 161 (74%) consultants joined in the last 10 years of whom 103 (64%) were UK trained. There were 91 leavers giving a staff turnover rate 42% (surgeons 56%, paediatric cardiologists 42%, ACHD cardiologists 29%). Of those, leaving 43% moved to work abroad (surgeons 55%, paediatric cardiologists 40%, ACHD cardiologists 67%). Among the 65 reported reasons for leaving 16 were financial, 9 for work life balance, 6 to working conditions within the National Health Service (NHS) and 12 related to the profession in the UK including six specifically highlighting the national review process.ConclusionsThere has been a high turnover rate of consultant staff within UK congenital cardiac services over the last 10 years with almost half of those leaving moving to work overseas. Financial reasons and pressures relating to working in the NHS or the specialty in the UK were commonly reported themes for leaving. This has major implications for future planning and staff retention within this specialised service.

scholarly journals Altered V-ATPase expression in renal intercalated cells isolated from B1 subunit-deficient mice by fluorescence-activated cell sorting

2013 ◽  
Vol 304 (5) ◽  
pp. F522-F532 ◽  
Author(s):  
Luca Vedovelli ◽  
John T. Rothermel ◽  
Karin E. Finberg ◽  
Carsten A. Wagner ◽  
Anie Azroyan ◽  
...  
Keyword(s):  
Cell Sorting ◽  
Collecting Duct ◽  
Egfp Expression ◽  
Intercalated Cells ◽  
Wild Type ◽  
Western Blots ◽  
Atpase Subunit ◽  
Protein Levels ◽  
Baseline Conditions ◽  
Deficient Mice

Unlike human patients with mutations in the 56-kDa B1 subunit isoform of the vacuolar proton-pumping ATPase (V-ATPase), B1-deficient mice (Atp6v1b1−/−) do not develop metabolic acidosis under baseline conditions. This is due to the insertion of V-ATPases containing the alternative B2 subunit isoform into the apical membrane of renal medullary collecting duct intercalated cells (ICs). We previously reported that quantitative Western blots (WBs) from whole kidneys showed similar B2 protein levels in Atp6v1b1−/− and wild-type mice (Păunescu TG, Russo LM, Da Silva N, Kovacikova J, Mohebbi N, Van Hoek AN, McKee M, Wagner CA, Breton S, Brown D. Am J Physiol Renal Physiol 293: F1915–F1926, 2007). However, WBs from renal medulla (including outer and inner medulla) membrane and cytosol fractions reveal a decrease in the levels of the ubiquitous V-ATPase E1 subunit. To compare V-ATPase expression specifically in ICs from wild-type and Atp6v1b1−/− mice, we crossed mice in which EGFP expression is driven by the B1 subunit promoter (EGFP-B1+/+ mice) with Atp6v1b1−/− mice to generate novel EGFP-B1−/− mice. We isolated pure IC populations by fluorescence-assisted cell sorting from EGFP-B1+/+ and EGFP-B1−/− mice to compare their V-ATPase subunit protein levels. We report that V-ATPase A, E1, and H subunits are all significantly downregulated in EGFP-B1−/− mice, while the B2 protein level is considerably increased in these animals. We conclude that under baseline conditions B2 upregulation compensates for the lack of B1 and is sufficient to maintain basal acid-base homeostasis, even when other V-ATPase subunits are downregulated.

How Frequent are Transfers of District and Block-Level Officers ?

1986 ◽  
Vol 11 (3) ◽  
pp. 215-224
Author(s):  
Girja Sharan ◽  
S. Narayanan
Keyword(s):  
Turnover Rate ◽  
Development Work ◽  
High Turnover ◽  
Minimum Duration ◽  
Duration Of Stay ◽  
Block Level

Development work is a team effort. The continued presence of the same team thus can be expected to be more fruitful. A high turnover rate of officials at district and lower levels is considered detrimental to development. This has been recognized and reflected in the setting up of norms of minimum duration of stay for various categories of officers dealing with development. But what is the reality on the ground? In this article, Girja Sharan and S Narayanan look into the frequency of transfers of officials over decades in two districts of Rajasthan and quantify the data, concluding that it is statistically certain that no team of Collector, Sub-Divisional Officer, Tehsildar, and Block Development Officer, initially appointed, would work for even a period of two years. Chances are just one in five that the team would last one for year!

scholarly journals Mitigating Effect of Psychological Capital on Employees’ Withdrawal Behavior in the Presence of Job Attitudes: Evidence From Five-Star Hotels in Malaysia

2021 ◽  
Vol 12 ◽  
Author(s):  
Zhen Yan ◽  
Zuraina D. Mansor ◽  
Wei C. Choo ◽  
Abdul R. Abdullah
Keyword(s):  
Job Satisfaction ◽  
Organizational Commitment ◽  
Turnover Intention ◽  
Turnover Rate ◽  
Psychological Capital ◽  
Job Attitudes ◽  
The Other ◽  
Equation Modeling ◽  
High Turnover ◽  
Other Hand

High turnover rate is one of the striking features of the hotel industry and one of the most significant challenges. High turnover rate causes substantial costs for recruitment, selection and training in hotels, on the other hand, it also leads to negative consequences such as the decline of organizational performance and service quality. Thus, it is necessary to search for the root causes of turnover and put forward solutions. This study was designed to examine the impact of psychological capital (PsyCap), organizational commitment (OC), and job satisfaction (JS) on turnover intention among hotel employees. Additionally, it aimed to test the mediating roles of job satisfaction (JS) and organizational commitment (OC). The data were obtained from 228 hotel customer-contact employees with a time lag of two weeks in three waves in Kuala Lumpur based on convenience sampling. A series of structural equation modeling analyses were utilized to investigate hypothesized relationships. The results reveal that there exists a significant and negative impact of PsyCap on employees’ turnover intention and this correlation is partially mediated through two job attitudes. That is to say, to retain hotel talents, five-star hotel management should take proper measures to help employees obtain and maintain positive psychological resources such as PsyCap, on the other hand, how to cultivate positive job attitudes and strengthen their sense of identification and belonging for their organizations is supposed to be more focused on.

Judicial Professional Associations: Fostering Judicial Reform Through Civil Society Development

2009 ◽  
Vol 33 (1) ◽  
pp. 48-62 ◽  
Author(s):  
Milica Golubovic
Keyword(s):  
Civil Society ◽  
Turnover Rate ◽  
Legal Education ◽  
Professional Associations ◽  
Judicial Reform ◽  
High Turnover ◽  
Administrative Capacity ◽  
History Of ◽  
Bar Association ◽  
Copy And Paste

AbstractThis article documents the history of judicial professional associations (the Judges' Association of Serbia, Prosecutors' Association of Serbia, and Magistrates' Association of Serbia) in Serbia from their early development in the mid-1990s through the present day. With a close focus on the associations' relationship with USAID implementing partner American Bar Association/Central Europe and Eurasian Law Initiative (ABA/CEELI), the article identifies the challenges to establishing sustainable judicial professional associations. These challenges include a lack of secure funding, low organizational and administrative capacity, a high turnover rate of volunteers and employees, reliance on foreign-generated 'copy-and-paste' activities that do not take local needs into account, and uneasy relationships with the local and central governments. Successes of the fledgling judicial professional associations are also noted, including the implementation of continuing legal education (CLE) seminars.

Identification of Crp as a novel regulator of the Std fimbrial expression in Salmonella

Microbiology ◽  
2021 ◽  
Author(s):  
Karine Dufresne ◽  
France Daigle
Keyword(s):  
Wild Type Strain ◽  
Distal Region ◽  
Transcriptional Factor ◽  
Major Influence ◽  
Wild Type ◽  
Content Type ◽  
Link Type ◽  
Serovar Typhimurium ◽  
Metabolic Regulators

The Salmonella enterica serovar Typhi genome contains 14 putative fimbrial systems. The Std fimbriae belong to the chaperone-usher family and its regulation has not been investigated in S. Typhi. Several regulators of Std were previously identified in the closely related serovar Typhimurium. We hypothesize that regulators of S. Typhimurium may be shared with S. Typhi, but that several other regulators remain to be discovered. Here, we describe the role of more than 50 different candidate regulators on std expression. Three types of regulators were investigated: known regulators in S. Typhimurium, in silico predicted regulators and virulence/metabolic regulators. Expression of std was determined in the regulator mutants and compared with the wild-type strain. Overall, 21 regulator mutations affect std promoter expression. The role of Crp, a newly identified factor for std expression, was further investigated. Crp acted as an activator of std expression on a distal region of the std promoter region. Together, our results demonstrate the major influence of Crp as a novel transcriptional factor on std promoter expression and later production of Std fimbriae in Salmonella .

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