DEVELOPMENT OF AN INDICATION SCHEME FOR AEROMONAS SALMONICIDA BACTERIA USING BACTERIOPHAGES

The causative agent of furunculosis Aeromonas salmonicida is widely spread around the world and usually affects many cold-water fish (trout), salmon, and less often fish from other families. Currently, there is no scheme for indicating the bacterium of the species A. salmonicida from objects of the external environment, using bacteriophages and accumulation media, which complicates the study of the distribution area of the mentioned microorganism and rapid indication of the pathogen. For this reason, the aim of the study was to develop a scheme for the indication of A. salmonicida bacteria using bacteriophages. To identify field strains of A. salmonicida, we examined 56 samples of water objects in Ulyanovsk and the Ulyanovsk region. Using the environment of accumulation of A. Sl.1 and the differential diagnostic environment A.Sl.2.7 A. salmonicida strains were isolated and typed from 56 samples. We have developed a scheme for the indication of A. salmonicida bacteria based on the modification of the phage titer increase reaction (RSF) using the accumulation medium A.Sl.1. This scheme allows detecting A. salmonicida in the amount of 103m.K./ml within 24 hours. The proposed scheme has the potential to be modified and applied to a whole range of microorganisms, sensitive and specific, allowing to detect bacteria in the substrate in a short time, in the presence of foreign microflora without isolation of pure cultures.

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4-hydroxyphenylpyruvate dioxygenase thermolability is responsible for temperature-dependent melanogenesis inAeromonas salmonicidasubsp.salmonicida

10.1101/324731 ◽

2018 ◽

Author(s):

Yunqian Qiao ◽

Jiao Wang ◽

He Wang ◽

Baozhong Chai ◽

Chufeng Rao ◽

...

Keyword(s):

Cold Water ◽

Biological Significance ◽

Adaptive Strategy ◽

Aeromonas Salmonicida ◽

Temperature Dependent ◽

Ideal Model ◽

Melanin Production ◽

Water Fish ◽

Insight Into

AbstractAeromonas salmonicidasubsp.salmonicida(A.s.s) is a major pathogen affecting fisheries worldwide. It is a well-known member of the pigmentedAeromonasspecies, which produces melanin at ≤ 22 °C. However, melanogenesis decreases as the culture temperature increases and is completely suppressed at 30-35 °C while bacterial growth is not affected. The mechanism and biological significance of this temperature-dependent melanogenesis are not clear. Heterologous expression of anA.s.s.4-hydroxyphenylpyruvate dioxygenase (HppD), the most crucial enzyme in the HGA-melanin synthesis pathway, results in thermosensitive pigmentation inEscherichia coli, suggesting that HppD plays a key role in this process. In the current study, we demonstrated that the extreme thermolability of HppD is responsible for the temperature-dependent melanization ofA.s.s.Substitutions in three residues, Ser18, Pro103, or Leu119 of HppD fromA.s.sincreases the thermolability of this enzyme and results in temperature-independent melanogenesis. Moreover, replacing the corresponding residues of HppD fromAeromonasmedia strain WS, which forms pigment independent of temperature, with those ofA.s.sHppD leads to thermosensitive melanogenesis. Structural analysis suggested that mutations at these sites, especially at position P103, can strengthen the secondary structure of HppD and greatly improve its thermal stability. In addition, we found that HppD sequences of allA.s.sisolates are identical and that two of the three residues are completely conserved withinA.s.sisolates, which clearly distinguishes these from otherAeromonasstrains. We suggest that this property represents an adaptive strategy to the psychrophilic lifestyle ofA.s.s.ImportanceAeromonas salmonicidasubsp.salmonicida(A.s.s) is the causative agent of furunculosis, a bacterial septicemia of cold water fish of theSalmonidaefamily. As it has a well-defined host range,A.s.shas become an ideal model to investigate the co-evolution of host and pathogen. For many pathogens, melanin production is associated with virulence. Although other species ofAeromonascan produce melanin,A.s.sis the only member of this genus that has been reported to exhibit temperature-dependent melanization. Here we demonstrate that thermosensitive melanogenesis inA.s.sstrains is due to the thermolability of 4-hydroxyphenylpyruvate dioxygenase (HppD). The strictly conservedhppDsequences amongA.s.sand the exclusive thermosensitive pigmentation of these strains might provide insight into the role of melanin in the adaptation to a particular host, and offer a novel molecular marker to readily differentiateA.s.sstrains from otherA. salmonicidasubspecies andAeromonasspecies.

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4-Hydroxyphenylpyruvate Dioxygenase Thermolability Is Responsible for Temperature-Dependent Melanogenesis inAeromonas salmonicidasubsp.salmonicida

Applied and Environmental Microbiology ◽

10.1128/aem.01926-18 ◽

2018 ◽

Vol 85 (1) ◽

Cited By ~ 1

Author(s):

Yunqian Qiao ◽

Jiao Wang ◽

He Wang ◽

Baozhong Chai ◽

Chufeng Rao ◽

...

Keyword(s):

Low Temperatures ◽

Cold Water ◽

Biological Significance ◽

Adaptive Strategy ◽

Homogentisic Acid ◽

Aeromonas Salmonicida ◽

Culture Temperature ◽

Temperature Dependent ◽

Content Type ◽

Water Fish

ABSTRACTAeromonas salmonicidasubsp.salmonicidais a major pathogen affecting fisheries worldwide and is a well-known pigmented member of theAeromonasgenus. This subspecies produces melanin at ≤22°C. However, melanogenesis decreases as the culture temperature increases and is completely suppressed at 30°C to 35°C, while bacterial growth is unaffected. The mechanism and biological significance of this temperature-dependent melanogenesis remain unclear. Heterologous expression of anA. salmonicidasubsp.salmonicida4-hydroxyphenylpyruvate dioxygenase (HppD), the most critical enzyme in the homogentisic acid (HGA)-melanin synthesis pathway, results in thermosensitive pigmentation inEscherichia coli, suggesting that HppD plays a key role in this process. In this study, we demonstrated that the thermolability of HppD is responsible for the temperature-dependent melanization ofA. salmonicidasubsp.salmonicida. Substitutions of three residues, S18T, P103Q, and L119P, inA. salmonicidasubsp.salmonicidaHppD increased the thermostability of this enzyme and resulted in temperature-independent melanogenesis. Moreover, the replacement of the corresponding residues in HppD fromAeromonas mediastrain WS, which forms pigment independent of temperature, with those ofA. salmonicidasubsp.salmonicidaHppD resulted in thermosensitive melanogenesis. A structural analysis suggested that mutations at these sites, especially at position P103, strengthen the secondary structure of HppD and greatly improve its thermal stability. Additionally, we found that the HppD sequences of allA. salmonicidasubsp.salmonicidaisolates were identical and that two of the three residues were clearly distinct from those of otherAeromonasstrains.IMPORTANCEAeromonas salmonicidasubsp. salmonicidais the causative agent of furunculosis, a bacterial septicemia of cold-water fish of theSalmonidaefamily. Although otherAeromonasspecies can produce melanin,A. salmonicidasubsp.salmonicidais the only member of this genus that has been reported to exhibit temperature-dependent melanization. Here, we demonstrated that thermosensitive melanogenesis inA. salmonicidasubsp.salmonicidastrains is due to the thermolability of 4-hydroxyphenylpyruvate dioxygenase (HppD). Additionally, we confirmed that this thermolabile HppD exhibited higher activity at low temperatures than its mesophilic homologues, suggesting this as an adaptive strategy of this enzyme to the psychrophilic lifestyle ofA. salmonicidasubsp.salmonicida. The strictly conservedhppDsequences amongA. salmonicidasubsp.salmonicidaisolates and the specific possession of P103 and L119 residues could be used as a reference for the identification ofA. salmonicidasubsp.salmonicidaisolates.

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Research on the Cement-Based Smart Lost-Circulation Control Material with Ti-Ni SMA

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.123-125.1015 ◽

2010 ◽

Vol 123-125 ◽

pp. 1015-1018 ◽

Cited By ~ 1

Author(s):

Qi Wang ◽

Lu Fei Tian ◽

Peng Song ◽

Zhen Liu

Keyword(s):

Smart Materials ◽

Volume Fraction ◽

Cold Water ◽

External Environment ◽

Hot Water ◽

Circulation Control ◽

Cement Slurry ◽

Control Material ◽

Lost Circulation ◽

Short Time

Different heat-treatments were carried out on the Ti-Ni shape memory alloy, alloy thread was made to straight line with the self-made alignment on 500 °C and then self-made angle training meter was used to train the alloys. Cement-based smart materials were prepared by the method of rolling agglomeration. Finally, indoor simulation experiment was carried out. The results show that the shape recovery ration becomes lower when quenching medium are hot-oil, hot-water, cold-oil and cold-water. The smart lost-circulation control material response quickly to external environment, the time from contact with external environment to the begin of distortion is less than or equal to five seconds, and to the end of distortion is less than or equal to sixty seconds.The best volume fraction for cement-based smart plugging material in cement slurry is 20%. Furthermore, the lost-circulation control material possesses the characteristics of a short time plugging and a strong pressure-bearing capability after plugging. And it improves the capacity of the ordinary cement-based smart lost-circulation control material.

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Epidemic Risk of Brucellosis in Modern conditions

Epidemiology and Vaccinal Prevention ◽

10.31631/2073-3046-2016-15-3-15-22 ◽

2016 ◽

Vol 15 (3) ◽

pp. 15-22 ◽

Cited By ~ 2

Author(s):

V. Yu. Okhapkina ◽

N. V. Pyatkova ◽

D. L. Pavlov ◽

A. A. Susloparov

Keyword(s):

High Risk ◽

Causative Agent ◽

Distribution Area ◽

Species Structure ◽

Brucella Species ◽

Natural Sources ◽

The World ◽

Natural Hosts ◽

Epidemic Risk

Under present conditions there is a high risk of an epidemic of brucellosis associated with the threat of the spread of the pathogen from many natural sources, as well as artificially as a result of bioterrorist actions. In spite of the vast complex of brucellosis eradication activities around the world, it still remains endemic in many regions of the world. The situation is exacerbated by the ecological spreading of the causative agent of brucellosis on the previously unusual species of natural hosts, accompanied by the emergence of new Brucella species, some of which poses a risk to humans. This paper summarizes the data on the distribution area of human pathogenic Brucella species, structure and level of incidence of brucellosis in different regions of our country and abroad, pathogenicity of representatives of different species and biotypes of Brucella for humans.

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The immune response of a warm water fish orange-spotted grouper (Epinephelus coioides) infected with a typical cold water bacterial pathogen Aeromonas salmonicida is AhR dependent

Developmental & Comparative Immunology ◽

10.1016/j.dci.2020.103779 ◽

2020 ◽

Vol 113 ◽

pp. 103779

Author(s):

Lixing Huang ◽

Weilu Qi ◽

Yanfei Zuo ◽

Siti Aisyah Alias ◽

Wei Xu

Keyword(s):

Immune Response ◽

Cold Water ◽

Bacterial Pathogen ◽

Aeromonas Salmonicida ◽

Warm Water ◽

Epinephelus Coioides ◽

Water Fish

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PERCEPTION AND INTERPRETATION OF CREATIVITY OF ALISHER NAVOI IN FRENCH ORIENTAL STUDIES

International journal of word art ◽

10.26739/2181-9297-2020-6-6 ◽

2020 ◽

Vol 6 (3) ◽

pp. 40-50

Author(s):

Mukhammadjon Holbekov ◽

Keyword(s):

The World ◽

Oriental Studies ◽

Short Time ◽

The Universe ◽

Precious Stones

The great Uzbek poet Alisher Navoi(1441-1501), during his lifetime, was widely known not only in his homeland, but also far beyond its borders. A contemporary and biographer of Navoi, the famous historian Hondemir, of course, not without some hyperbole, wrote: "He (Navoi -M.Kh.) in a short time took the cane of primacy from his peers; the fame of his talents spread to all ends of the world, and the stories of the firmness of his noble mind from mouth to mouth were innumerable.The pearls of his poetry adorned the leaves of the Book of Fates, the precious stones of his poetry filled the shells of the universe with pearls of beauty

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A Sustainable Approach for Organisational using Strategic Management

International Journal of Sustainable Construction Engineering Technology ◽

10.30880/ijie.2020.11.02.030 ◽

2020 ◽

Vol 11 (2) ◽

Author(s):

Abdulla Almazrouei ◽

◽

Azlina Md Yassin ◽

Keyword(s):

Mortality Rate ◽

Strategic Planning ◽

Strategic Management ◽

Crime Rate ◽

External Environment ◽

Police Department ◽

Public Institutions ◽

Abu Dhabi ◽

The Public ◽

The World

Strategic management have gained popularity in the public institutions to foster good delivery service to the public. The strategic planning enables organizations to establish a strategic match between the internal competency, resources and external environment. Majority of the successful organizations across the world use strategic management and planning as a tool that enables to optimize the operations and achieve maximum productivity with the resources. This paper reviewed on strategic management for organisations in Abu Dhabi especially for Abu Dhabi Police (ADP) force. It presents three strategic management theories which can be adopted by an organisation. This would help the organisation such as police department to reduce the increasing crime rate and mortality rate in UAE.

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Efficacy of compressed sodium chloride (CSC) against E. coli and Candida auris in minutes and methods improvement for testing

Scientific Reports ◽

10.1038/s41598-020-79212-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Lan N. Truong ◽

Brayden D. Whitlock

Keyword(s):

Sodium Chloride ◽

Improved Method ◽

Candida Auris ◽

Antimicrobial Surfaces ◽

E Coli ◽

Route Of Transmission ◽

The World ◽

Short Time ◽

First Time ◽

Time Point

AbstractControlling infections has become one of the biggest problems in the world, whether measured in lives lost or money spent. This is worsening as pathogens continue becoming resistant to therapeutics. Antimicrobial surfaces are one strategy being investigated in an attempt to decrease the spread of infections through the most common route of transmission: surfaces, including hands. Regulators have chosen two hours as the time point at which efficacy should be measured. The objectives of this study were to characterize the new antimicrobial surface compressed sodium chloride (CSC) so that its action may be understood at timepoints more relevant to real-time infection control, under two minutes; to develop a sensitive method to test efficacy at short time points; and to investigate antifungal properties for the first time. E. coli and Candida auris are added to surfaces, and the surfaces are monitored by contact plate, or by washing into collection vats. An improved method of testing antimicrobial efficacy is reported. Antimicrobial CSC achieves at least 99.9% reduction of E. coli in the first two minutes of contact, and at least 99% reduction of C. auris in one minute.

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