scholarly journals Melanin Produced by the Fast-Growing Marine Bacterium Vibrio natriegens through Heterologous Biosynthesis: Characterization and Application

2019 ◽  
Vol 86 (5) ◽  
Author(s):  
Zheng Wang ◽  
Tanya Tschirhart ◽  
Zachary Schultzhaus ◽  
Erin E. Kelly ◽  
Amy Chen ◽  
...  

ABSTRACT Melanin is a pigment produced by organisms throughout all domains of life. Due to its unique physicochemical properties, biocompatibility, and biostability, there has been an increasing interest in the use of melanin for broad applications. In the vast majority of studies, melanin has been either chemically synthesized or isolated from animals, which has restricted its use to small-scale applications. Using bacteria as biocatalysts is a promising and economical alternative for the large-scale production of biomaterials. In this study, we engineered the marine bacterium Vibrio natriegens, one of the fastest-growing organisms, to synthesize melanin by expressing a heterologous tyrosinase gene and demonstrated that melanin production was much faster than in previously reported heterologous systems. The melanin of V. natriegens was characterized as a polymer derived from dihydroxyindole-2-carboxylic acid (DHICA) and, similarly to synthetic melanin, exhibited several characteristic and useful features. Electron microscopy analysis demonstrated that melanin produced from V. natriegens formed nanoparticles that were assembled as “melanin ghost” structures, and the photoprotective properties of these particles were validated by their protection of cells from UV irradiation. Using a novel electrochemical reverse engineering method, we observed that melanization conferred redox activity to V. natriegens. Moreover, melanized bacteria were able to quickly adsorb the organic compound trinitrotoluene (TNT). Overall, the genetic tractability, rapid division time, and ease of culture provide a set of attractive properties that compare favorably to current E. coli production strains and warrant the further development of this chassis as a microbial factory for natural product biosynthesis. IMPORTANCE Melanins are macromolecules that are ubiquitous in nature and impart a large variety of biological functions, including structure, coloration, radiation resistance, free radical scavenging, and thermoregulation. Currently, in the majority of investigations, melanins are either chemically synthesized or extracted from animals, which presents significant challenges for large-scale production. Bacteria have been used as biocatalysts to synthesize a variety of biomaterials due to their fast growth and amenability to genetic engineering using synthetic biology tools. In this study, we engineered the extremely fast-growing bacterium V. natriegens to synthesize melanin nanoparticles by expressing a heterologous tyrosinase gene with inducible promoters. Characterization of the melanin produced from V. natriegens-produced tyrosinase revealed that it exhibited physical and chemical properties similar to those of natural and chemically synthesized melanins, including nanoparticle structure, protection against UV damage, and adsorption of toxic compounds. We anticipate that producing and controlling melanin structures at the nanoscale in this bacterial system with synthetic biology tools will enable the design and rapid production of novel biomaterials for multiple applications.

2021 ◽  
Vol 2115 (1) ◽  
pp. 012026
Author(s):  
Sonam Solanki ◽  
Gunendra Mahore

Abstract In the current process of producing vermicompost on a large-scale, the main challenge is to keep the worms alive. This is achieved by maintaining temperature and moisture in their living medium. It is a difficult task to maintain these parameters throughout the process. Currently, this is achieved by building infrastructure but this method requires a large initial investment and long-run maintenance. Also, these methods are limited to small-scale production. For large-scale production, a unit is developed which utilises natural airflow with water and automation. The main aim of this unit is to provide favourable conditions to worms in large-scale production with very low investment and minimum maintenance in long term. The key innovation of this research is that the technology used in the unit should be practical and easy to adopt by small farmers. For long-term maintenance of the technology lesser number of parts are used.


2019 ◽  
Vol 7 (2) ◽  
pp. 147-161 ◽  
Author(s):  
Maria L.A.D. Lestari ◽  
Rainer H. Müller ◽  
Jan P. Möschwitzer

Background: Miniaturization of nanosuspensions preparation is a necessity in order to enable proper formulation screening before nanosizing can be performed on a large scale. Ideally, the information generated at small scale is predictive for large scale production. Objective: This study was aimed to investigate the scalability when producing nanosuspensions starting from a 10 g scale of nanosuspension using low energy wet ball milling up to production scales of 120 g nanosuspension and 2 kg nanosuspension by using a standard high energy wet ball milling operated in batch mode or recirculation mode, respectively. Methods: Two different active pharmaceutical ingredients, i.e. curcumin and hesperetin, have been used in this study. The investigated factors include the milling time, milling speed, and the type of mill. Results: Comparable particle sizes of about 151 nm to 190 nm were obtained for both active pharmaceutical ingredients at the same milling time and milling speed when the drugs were processed at 10 g using low energy wet ball milling or 120 g using high energy wet ball milling in batch mode, respectively. However, an adjustment of the milling speed was needed for the 2 kg scale produced using high energy wet ball milling in recirculation mode to obtain particle sizes comparable to the small scale process. Conclusion: These results confirm in general, the scalability of wet ball milling as well as the suitability of small scale processing in order to correctly identify the most suitable formulations for large scale production using high energy milling.


2020 ◽  
Vol 175 ◽  
pp. 10008
Author(s):  
Thi Hoai Nguyen ◽  
Duc Luan Nguyen

In this paper, the authors analyze the current situation of agricultural production in Vietnam and affirm that fragmentation is one of the basic causes leading to ineffective potentials and low labor productivity. Based on this, the authors propose a number of solutions to convert small-scale production to large-scale production in order to improve labor productivity and optimally exploit resources in the agricultural sector in Vietnam today.


2011 ◽  
Vol 77 (21) ◽  
pp. 7508-7516 ◽  
Author(s):  
Jiequn Wu ◽  
Qinglin Zhang ◽  
Wei Deng ◽  
Jiangchao Qian ◽  
Siliang Zhang ◽  
...  

ABSTRACTLarge-scale production of erythromycin A (Er-A) relies on the organismSaccharopolyspora erythraea, in which lack of a typicalattBsite largely impedes the application of phage ΦC31 integrase-mediated recombination into site-specific engineering. We herein report construction of an artificialattBsite in an industrialS. erythraeastrain, HL3168 E3, in an effort to break the bottleneck previously encountered during genetic manipulation mainly from homologous or unpredictable nonspecific integration. Replacement of a cryptic gene,nrps1-1, with a cassette containing eightattBDNA sequences did not affect the high Er-producing ability, setting the stage for precisely engineering the industrial Er-producing strain for foreign DNA introduction with a reliable conjugation frequency. Transfer of either exogenous or endogenous genes of importance to Er-A biosynthesis, including theS-adenosylmethionine synthetase gene for positive regulation,vhbfor increasing the oxygen supply, and two tailoring genes,eryKanderyG, for optimizing the biotransformation at the late stage, was achieved by taking advantage of this facility, allowing systematic improvement of Er-A production as well as elimination of the by-products Er-B and Er-C in fermentation. The strategy developed here can generally be applicable to other strains that lack theattBsite.


1992 ◽  
Vol 24 (1) ◽  
pp. 27-47 ◽  
Author(s):  
John Smail

Between the Civil War and the Industrial Revolution, four generations of the Stansfield family lived in Halifax—an upland parish in the West Riding of Yorkshire. Although its politics were calm, the century and a half between England's two great “revolutions” was not devoid of change in other respects. Significant social, economic, and cultural developments during this period laid the foundations for the ferment of the Industrial Revolution. The history of the Stansfield family is an excellent illustration of these changes, for there was a world of difference between the great-grandfather, Josias Stansfield, who was in his prime at the Restoration, and his great-grandsons, George and David Stansfield, who were in their primes a century later.For his part, Josias was recognizably a man of the middling sort. A yeoman engaged in farming and small-scale textile production, his economic activities and his social standing place him in the ranks of families who fell between the few gentlemen who lived in the area and the mass of simple artisans and laborers who had to struggle just to survive. Josias's great-grandsons, George and David Stansfield lived in a different world. By the mid-eighteenth century, Halifax's textile industry was increasingly dominated by large-scale production of which George's large putting-out concern and David's substantial export business were typical. George and David's social position was also quite different. No longer merely comfortable, these two second cousins were among the wealthiest residents of their respective townships, and they had assumed an appropriately significant share of the political and social leadership in the parish.


2020 ◽  
Vol 8 (6) ◽  
pp. 5265-5268

The work in this paper is focused , about the sugarcane harvesting machine, as India is considered as one of the higher consumers and producers of sugarcane and its by products and to due to huge population, there is a high demand of sugarcane and to meet the demand of population, large scale production has to be adopted, hence for farming and harvesting the sugarcane an automated, low cost harvester is necessary for the farmers to reduce the efforts of sugarcane harvesting and to increase the rate of sugar cane cutting. This machine will be helpful for the farmers having both small and big farms, the work on this paper was carried to identify the major options along with the opportunities and major chances for future enhancement in the field of agriculture industries.


Author(s):  
C. Ferreras ◽  
B. Pascual-Miguel ◽  
C. Mestre-Durán ◽  
A. Navarro-Zapata ◽  
L. Clares-Villa ◽  
...  

Syndrome coronavirus 2 (SARS-CoV-2) pandemic is causing a second outbreak significantly delaying the hope for the virus’ complete eradication. In the absence of effective vaccines, we need effective treatments with low adverse effects that can treat hospitalized patients with COVID-19 disease. In this study, we determined the existence of SARS-CoV-2-specific T cells within CD45RA– memory T cells in the blood of convalescent donors. Memory T cells can respond quickly to infection and provide long-term immune protection to reduce the severity of COVID-19 symptoms. Also, CD45RA– memory T cells confer protection from other pathogens encountered by the donors throughout their life. It is of vital importance to resolve other secondary infections that usually develop in patients hospitalized with COVID-19. We found SARS-CoV-2-specific memory T cells in all of the CD45RA– subsets (CD3+, CD4+, and CD8+) and in the central memory and effector memory subpopulations. The procedure for obtaining these cells is feasible, easy to implement for small-scale manufacture, quick and cost-effective, involves minimal manipulation, and has no GMP requirements. This biobank of specific SARS-CoV-2 memory T cells would be immediately available “off-the-shelf” to treat moderate/severe cases of COVID-19, thereby increasing the therapeutic options available for these patients.


Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 682
Author(s):  
Haroon-Ur Rashid ◽  
Muhammad Ali ◽  
Mahidur R. Sarker ◽  
Sawal Hamid Md Ali ◽  
Naseem Akhtar ◽  
...  

The promising chemical, mechanical, and electrical properties of silver from nano scale to bulk level make it useful to be used in a variety of applications in the biomedical and electronic fields. Recently, several methods have been proposed and applied for the small-scale and mass production of silver in the form of nanoparticles, nanowires, and nanofibers. In this research, we have proposed a novel method for the fabrication of silver nano fibers (AgNFs) that is environmentally friendly and can be easily deployed for large-scale production. Moreover, the proposed technique is easy for device fabrication in different applications. To validate the properties, the synthesized silver nanofibers have been examined through Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-Ray diffraction (XRD). Further, the synthesized silver nanofibers have been deposited over sensors for Relative humidity (RH), Ammonia (NH3), and temperature sensing applications. The sensor was of a resistive type, and found 4.3 kΩ for relative humidity (RH %) 30–90%, 400 kΩ for NH3 (40000 ppm), and 5 MΩ for temperature sensing (69 °C). The durability and speed of the sensor verified through repetitive, response, and recovery tests of the sensor in a humidity and gas chamber. It was observed that the sensor took 13 s to respond, 27 s to measure the maximum value, and took 33 s to regain its minimum value. Furthermore, it was observed that at lower frequencies and higher concentration of NH3, the response of the device was excellent. Furthermore, the device has linear and repetitive responses, is cost-effective, and is easy to fabricate.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Agnieszka Dudkiewicz ◽  
William Hayes ◽  
Bukola Onarinde

PurposeThe purpose of this pilot-scale study was to compare the quality of traditionally manufactured butters from local, small British producers with the quality of butters that are produced industrially.Design/methodology/approachButter samples were obtained after supervised site inspections of three traditional-butter manufacturers and one large-scale butter producer. The samples were subject to initial microbiological, chemical and sensory testing, followed by a refrigerated shelf-life study over 24 weeks.FindingsTraditional butters matched or exceeded the sensory quality of industrial butters, but spoilage microorganisms tended to grow faster on traditional butters. This seemed to be related to poorer water droplet dispersion in the manufacture of some of the traditionally made butters. Visible mould appeared on two of the traditional butters after eight weeks, but this occurred well after the nominal “best before” date.Originality/valueProlonged lockdowns due to the current coronavirus disease (COVID-19) pandemic pose a threat to the food supply chain, and food produced by local manufacturers may become increasingly important. However, are foods produced by local small-scale manufacturers of a quality comparable to that produced using large-scale production facilities? To the best of the authors' knowledge, there is no comparative study of the quality and shelf-life of traditionally-produced and industrially-produced butters. The current work presents such a comparison together with an outline of how the process of traditional butter-making differs from commercial production in Britain.


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