scholarly journals A Novel Glutathione S-Transferase Gtt2 Class (VpGSTT2) Is Found in the Genome of the AHPND/EMS Vibrio parahaemolyticus Shrimp Pathogen

Toxins ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 664
Author(s):  
Ignacio Valenzuela-Chavira ◽  
David O. Corona-Martinez ◽  
Karina D. Garcia-Orozco ◽  
Melissa Beltran-Torres ◽  
Filiberto Sanchez-Lopez ◽  
...  
Keyword(s):  
Water Molecule ◽  
Vibrio Parahaemolyticus ◽  
Catalytic Mechanism ◽  
Specific Activity ◽  
Sulfhydryl Group ◽  
Biochemical Properties ◽  
Titration Calorimetry ◽  
Primary Role ◽  
Early Mortality Syndrome ◽  
Acute Hepatopancreatic Necrosis Disease

Glutathione S-transferases are a family of detoxifying enzymes that catalyze the conjugation of reduced glutathione (GSH) with different xenobiotic compounds using either Ser, Tyr, or Cys as a primary catalytic residue. We identified a novel GST in the genome of the shrimp pathogen V. parahaemolyticus FIM- S1708+, a bacterial strain associated with Acute Hepatopancreatic Necrosis Disease (AHPND)/Early Mortality Syndrome (EMS) in cultured shrimp. This new GST class was named Gtt2. It has an atypical catalytic mechanism in which a water molecule instead of Ser, Tyr, or Cys activates the sulfhydryl group of GSH. The biochemical properties of Gtt2 from Vibrio parahaemolyticus (VpGSTT2) were characterized using kinetic and crystallographic methods. Recombinant VpGSTT2 was enzymatically active using GSH and CDNB as substrates, with a specific activity of 5.7 units/mg. Low affinity for substrates was demonstrated using both Michaelis–Menten kinetics and isothermal titration calorimetry. The crystal structure showed a canonical two-domain structure comprising a glutathione binding G-domain and a hydrophobic ligand H domain. A water molecule was hydrogen-bonded to residues Thr9 and Ser 11, as reported for the yeast Gtt2, suggesting a primary role in the reaction. Molecular docking showed that GSH could bind at the G-site in the vicinity of Ser11. G-site mutationsT9A and S11A were analyzed. S11A retained 30% activity, while T9A/S11A showed no detectable activity. VpGSTT2 was the first bacterial Gtt2 characterized, in which residues Ser11 and Thr9 coordinated a water molecule as part of a catalytic mechanism that was characteristic of yeast GTT2. The GTT2 family has been shown to provide protection against metal toxicity; in some cases, excess heavy metals appear in shrimp ponds presenting AHPND/EMS. Further studies may address whether GTT2 in V. parahaemolyticus pathogenic strains may provide a competitive advantage as a novel detoxification mechanism.

scholarly journals Prevalence and Antimicrobial Resistance of Vibrio spp. in Retail and Farm Shrimps in Ecuador

2015 ◽  
Vol 78 (11) ◽  
pp. 2089-2092 ◽  
Author(s):  
L. SPERLING ◽  
T. ALTER ◽  
S. HUEHN
Keyword(s):  
Vibrio Parahaemolyticus ◽  
Antimicrobial Agents ◽  
Vibrio Vulnificus ◽  
Common Species ◽  
Retail Markets ◽  
Early Mortality Syndrome ◽  
Resistance Patterns ◽  
Acute Hepatopancreatic Necrosis Disease ◽  
Shrimp Farms ◽  
Vibrio Spp

The aim of this study was to investigate the prevalence of Vibrio spp. in shrimp at retail and in shrimp farms in Ecuador and to determine the antimicrobial agent resistance patterns of farm isolates. The presence of genes linked to early mortality syndrome (EMS) or acute hepatopancreatic necrosis disease (AHPND) also was evaluated. Vibrio spp. were isolated from retail shrimps in Cuenca, Ecuador, and farm shrimps originating from provinces El Oro and Guayas, Ecuador. A total of 229 shrimp samples were collected, of which 71 originated from retail markets in Cuenca and 158 came from shrimp farms. Overall, 219 (95.6%) samples tested positive for Vibrio spp. Vibrio parahaemolyticus (80.8%) was the most common species detected, followed by Vibrio alginolyticus (50.2%), Vibrio cholerae (11.3%), and Vibrio vulnificus (3.5%). None of the V. parahaemolyticus isolates carried the virulence-associated tdh and trh genes. In V. parahaemolyticus shrimp farm isolates, high resistance was found to ampicillin (92.2%), and intermediate resistance was found to tetracycline (51.3%) and amikacin (22.1%). Of the V. parahaemolyticus strains, 68 were resistant to at least three antimicrobial agents, and 2 were resistant to seven antimicrobial agents simultaneously. Up to 18 resistant isolates were found for V. alginolyticus, whereas V. vulnificus and V. cholerae isolates were more susceptible. None of the V. parahaemolyticus isolates carried the EMS-AHPND plasmid. The results of this study revealed the ubiquitous occurrence of Vibrio spp. in shrimps at retail and on shrimp farms in Ecuador.

scholarly journals A Natural Vibrio parahaemolyticus ΔpirAVppirBVp+ Mutant Kills Shrimp but Produces neither PirVp Toxins nor Acute Hepatopancreatic Necrosis Disease Lesions

2017 ◽  
Vol 83 (16) ◽  
Author(s):  
Kornsunee Phiwsaiya ◽  
Walaiporn Charoensapsri ◽  
Suwimon Taengphu ◽  
Ha T. Dong ◽  
Pakkakul Sangsuriya ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Vibrio Parahaemolyticus ◽  
Gene Sequence ◽  
Culture Broth ◽  
Upstream Region ◽  
Enzyme Linked Immunosorbent Assay ◽  
Content Type ◽  
Early Mortality Syndrome ◽  
Reverse Transcription Pcr ◽  
Acute Hepatopancreatic Necrosis Disease

ABSTRACT Acute hepatopancreatic necrosis disease (AHPND) of shrimp is caused by Vibrio parahaemolyticus isolates (VPAHPND isolates) that harbor a pVA plasmid encoding toxins PirA Vp and PirB Vp . These are released from VPAHPND isolates that colonize the shrimp stomach and produce pathognomonic AHPND lesions (massive sloughing of hepatopancreatic tubule epithelial cells). PCR results indicated that V. parahaemolyticus isolate XN87 lacked pirA Vp but carried pirB Vp . Unexpectedly, Western blot analysis of proteins from the culture broth of XN87 revealed the absence of both toxins, and the lack of PirB Vp was further confirmed by enzyme-linked immunosorbent assay. However, shrimp immersion challenge with XN87 resulted in 47% mortality without AHPND lesions. Instead, lesions consisted of collapsed hepatopancreatic tubule epithelia. In contrast, control shrimp challenged with typical VPAHPND isolate 5HP gave 90% mortality, accompanied by AHPND lesions. Sequence analysis revealed that the pVA plasmid of XN87 contained a mutated pirA Vp gene interrupted by the out-of-frame insertion of a transposon gene fragment. The upstream region and the beginning of the original pirA Vp gene remained intact, but the insertion caused a 2-base reading frameshift in the remainder of the pirA Vp gene sequence and in the downstream pirB Vp gene sequence. Reverse transcription-PCR and sequencing of 5HP revealed a bicistronic pirAB Vp mRNA transcript that was not produced by XN87, explaining the absence of both toxins in its culture broth. However, the virulence of XN87 revealed that some V. parahaemolyticus isolates carrying mutant pVA plasmids that produce no Pir Vp toxins can cause mortality in shrimp in ponds experiencing an outbreak of early mortality syndrome (EMS) but may not have been previously recognized to be AHPND related because they did not cause pathognomonic AHPND lesions. IMPORTANCE Shrimp acute hepatopancreatic necrosis disease (AHPND) is caused by Vibrio parahaemolyticus isolates (VPAHPND isolates) that harbor the pVA1 plasmid encoding toxins PirA Vp and PirB Vp . The toxins are produced in the shrimp stomach but cause death by massive sloughing of hepatopancreatic tubule epithelial cells (pathognomonic AHPND lesions). V. parahaemolyticus isolate XN87 harbors a mutant pVA plasmid that produces no Pir toxins and does not cause AHPND lesions but still causes ∼50% shrimp mortality. Such isolates may cause a portion of the mortality in ponds experiencing an outbreak of EMS that is not ascribed to VPAHPND. Thus, they pose to shrimp farmers an additional threat that would be missed by current testing for VPAHPND. Moribund shrimp from ponds experiencing an outbreak of EMS that exhibit collapsed hepatopancreatic tubule epithelial cells can serve as indicators for the possible presence of such isolates, which can then be confirmed by additional PCR tests for the presence of a pVA plasmid.

scholarly journals The infection of Vibrio parahaemolyticus in shrimp and human

2018 ◽  
Vol 1 (1) ◽  
pp. 44 ◽  
Author(s):  
Rian Ka Praja
Keyword(s):  
Vibrio Parahaemolyticus ◽  
Animal Health ◽  
Alternative Therapy ◽  
Penaeus Monodon ◽  
Early Mortality ◽  
Economic Losses ◽  
Early Mortality Syndrome ◽  
Thermostable Direct Hemolysin ◽  
Acute Hepatopancreatic Necrosis Disease ◽  
Very High

<p class="15" align="justify"><em>Vibrio parahaemolyticus</em> is an aquatic zoonotic agent that can threaten human and aquaculture animal health. Humans can be infected by consuming contaminated raw seafood or wound-related infections. Generally infection of <em>V. parahemolyticus</em> is orally transmitted and causes gastroenteritis in humans while in aquaculture animals especially shrimp can cause Acute Hepatopancreatic Necrosis Disease (AHPND) or Early Mortality Syndrome (EMS) with a very high mortality rate and cause economic losses. Shrimp species susceptible to infection are <em>Litopenaeus vannamei, Penaeus monodon,</em> and <em>P. chinensis</em>. <em>V. parahaemolyticus</em> produces several toxins in human disease such as thermostable direct hemolysin (TDH), TDH-related haemolysin (TRH), and thermolabile hemolysin (TLH). Meanwhile, Photorabdus insect-related (Pir) toxins consisting of PirA<sup>vp</sup> and PirB<sup>vp</sup> are the toxins associated with AHPND in shrimp. The genes that encode the toxin are used as targets to diagnose <em>V. parahaemolyticus</em> pathogens molecularly. Until now the treatment of <em>V. parahaemolyticus</em> infection is using antibiotics and fluid therapy, but there were <em>V. parahaemolyticus</em> isolates from aquaculture that have been resistant to antibiotics so that the use of antibiotics in aquaculture must be controlled and the use of alternative therapy are very important to be developed to control <em>V. parahaemolyticus</em> infection.</p><p class="15" align="justify"> </p><p>Keywords: <em>V. parahaemolyticus</em>, zoonotic, gastroenteritis, Acute Hepatopancreatic Necrosis Disease (AHPND), Early Mortality Syndrome (EMS).</p>

scholarly journals Effects of salinity and shaking condition on the growth and virulence of Vibrio parahaemolyticus

2020 ◽  
Vol 18 (2) ◽  
pp. 349-362
Author(s):  
Tran Ngoc My Hanh ◽  
Tran Van Nhi ◽  
Nguyen Thi Thu Hoai
Keyword(s):  
Vibrio Parahaemolyticus ◽  
Extracellular Enzymes ◽  
Brain Heart Infusion ◽  
Halophilic Bacterium ◽  
Chitinase Activity ◽  
Early Mortality Syndrome ◽  
Potential Pathogen ◽  
Salinity Increase ◽  
The One ◽  
Acute Hepatopancreatic Necrosis Disease

Vibrio parahaemolyticus is a Gram-negative halophilic bacterium that is found in estuarine, marine and coastal environment. This organism is the major causative agent of Early Mortality Syndrome (EMS) or Acute Hepatopancreatic Necrosis Disease (AHPND) which resulted in serious damages to cultured shrimp industry. Understanding the effect of environmental factors on the growth and virulence of this potential pathogen would be beneficial for preventing its outbreak. In this study, the growth and virulence of V. parahaemolyticus was examined under different salinity and shaking condition. V. parahaemolyticus XN9 was cultured in Brain Heart Infusion (BHI) medium with different sodium chloride concentrations (2.0, 2.5 and 3.0%) and different shaking conditions (0, 120 and 240 rpm). The growth of the bacterium was recorded over 8h and six extracellular enzymes of V. parahaemolyticus XN9 including caseinase, hemolysin, lecithinase, lipase, gelatinase, chitinase were investigated using agar-based method. The growth of V. parahaemolyticus was varied among different salinity and shaking conditions. It showed the best growth at 2.0% NaCl and 240 rpm. No change in the enzymatic activity (EA) of the tested extracellular enzymes was observed while changing salinity except the significant decline of gelatinase from 3.49±0.19 to 2.77±0.17 mm following salinity increase (p < 0.05). On the other hand, regarding shaking condition, lipase was the one to increase its activity significantly following the increase of shaking speed (p < 0.05). While caseinase, lecithinase, gelatinase and lipase were well expressed in V. parahaemolyticus, no hemolytic and chitinase activity was observed in any tested conditions. In summary, our study showed that 2.0 % NaCl and 240 rpm shaking promoted the best growth of V. parahaemolyticus and resulted in highest activity of gelatinase and lipase in this bacterium.

scholarly journals NGHIÊN CỨU KHẢ NĂNG KHÁNG VI KHUẨN Vibrio spp. GÂY BỆNH HOẠI TỬ GAN TỤY CẤP (AHPND) TRÊN TÔM CHÂN TRẮNG (Litopenaeus vannamei) CỦA DỊCH CHIẾT TỪ CÂY CHÓ ĐẺ THÂN XANH (Phyllanthus amarus Schum)

2019 ◽  
Vol 128 (1E) ◽  
pp. 99-106
Author(s):  
Trần Vinh Phương ◽  
Hoàng Thị Ngọc Hân ◽  
Đặng Thanh Long ◽  
Phạm Thị Hải Yến ◽  
Nguyễn Quang Linh
Keyword(s):  
Litopenaeus Vannamei ◽  
Vibrio Parahaemolyticus ◽  
Early Mortality ◽  
Phyllanthus Amarus ◽  
Early Mortality Syndrome ◽  
Acute Hepatopancreatic Necrosis Disease ◽  
Vibrio Spp

Kết quả nghiên cứu nhằm xác định khả năng kháng khuẩn của dịch chiết từ cây chó đẻ thân xanh (Phyllanthus amarus); nồng độ ức chế tối thiểu (MIC) và nồng độ tiêu diệt tối thiểu (MBC) trên 2 chủng vi khuẩn Vibrio parahaemolitycus (K15) và Vibrio sp. (VT33) ở mật độ 106 CFU/mL gây bệnh hoại tử gan tụy cấp (Acute Hepatopancreatic Necrosis Disease –AHPND) còn được gọi là hội chứng tôm chết sớm (Early Mortality Syndrome - EMS) trên tôm chân trắng (Litopenaeus vannamei) nuôi tại Thừa Thiên Huế, kết quả ban đầu ghi nhận: dịch chiết được chiết xuất dạng cao từ cây chó đẻ thân xanh (P. amarus) có khả năng kháng cả 2 chủng Vibrio parahaemolitycus (K15) và Vibrio sp. (VT33) thử nghiệm từ nồng độ 250 đến 1.000 mg/mL, thể hiện ở đường kính vòng kháng khuẩn dao động từ 16,60–21,40 mm đối với chủng Vibrio parahaemolitycus (K15) và từ 17,60 – 23,60 mm đối với Vibrio sp. (VT33). Kết quả cũng xác định hiệu quả của dịch chiết trên 2 chủng Vibrio parahaemolyticus (K15) và Vibrio sp. (VT123) thể hiện giá trị MIC và MBC tương ứng đạt 125 mg/mL và 500 mg/mL; 62,5 và 500 mg/mL.

scholarly journals POTENTIAL GROWTH INHIBITION ACTIVITY OF FECAL MATERIALS, MUCUS AND CULTURED WATER OF TILAPIA OREOCHROMIS NILOTICUS ON ACUTE HEPATOPANCREATIC NECROSIS DISEASE (AHPND) - CAUSING PATHOGEN VIBRIO PARAHAEMOLYTICUS

2018 ◽  
Vol 15 (4) ◽  
pp. 777-784
Author(s):  
Le Ngoc Phuong Thanh ◽  
Ho Hai Co ◽  
Trinh Thi Truc Ly ◽  
Hoang Tung ◽  
Bui Thi Hong Hanh
Keyword(s):  
Oreochromis Niloticus ◽  
Vibrio Parahaemolyticus ◽  
Challenge Test ◽  
Negative Control ◽  
Shrimp Farming ◽  
Diffusion Method ◽  
Potential Growth ◽  
Intrinsic Factors ◽  
Early Mortality Syndrome ◽  
Acute Hepatopancreatic Necrosis Disease

Shrimp farming plays a key role in economy of many countries all over the world. Unfortunately, a disease called Acute Hepatopancreatic Necrosis Disease (AHPND) or Early Mortality Syndrome (EMS) caused by Vibrio parahaemolyticus spreading from Asia to Central America costs shrimp industry billions of dollars annually. In the past few years, scientists from multi-disciplinary field collaborated to find out a solution for this disease. Until now, there are not any effective approaches to prevent and cure this disease. However, co-culturing shrimp with tilapia was carried out to limit the outbreak of AHPND in farm scale in many countries. Some previous studies also mentioned the benefits of this farming method to prevent other pathogens. The aim of this research is to determine whether intrinsic factors or cultured water of tilapia play role in inhibition of V. parahaemolyticus – pathogen causing AHPND. These factors include: mucus on tilapia gill and skin, tilapia fecal material, and microbiota or dissolved chemicals in culturing of tilapia. Anti-V. parahaemolyticus activity of tilapia (Oreochromis niloticus) fresh and overnight incubated feces and mucus were tested using agar well diffusion method. The effectiveness of feces and mucus inhibition was not clear, both of samples generated a weak inhibition on V. parahaemolyticus. Determination of V. parahaemolyticus inhibiting factor of tilapia cultured water using challenge test showed that dissolved compounds (smaller than 0.22 µm) inhibited the growth of V. parahaemolyticus. The presence of these compounds in tilapia-cultured water reduced V. parahaemolyticus to 17 times lower than that of the negative control with the seawater alone within the first three hours post challenge.

scholarly journals Biochemical characterization of specific Alanine Decarboxylase (AlaDC) and its ancestral enzyme Serine Decarboxylase (SDC) in tea plants (Camellia sinensis)

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Peixian Bai ◽  
Liyuan Wang ◽  
Kang Wei ◽  
Li Ruan ◽  
Liyun Wu ◽  
...  
Keyword(s):  
Gene Duplication ◽  
Camellia Sinensis ◽  
Biochemical Characterization ◽  
Specific Activity ◽  
Protein Sequences ◽  
Biochemical Properties ◽  
High Similarity ◽  
New Gene ◽  
Tea Plants

Abstract Background Alanine decarboxylase (AlaDC), specifically present in tea plants, is crucial for theanine biosynthesis. Serine decarboxylase (SDC), found in many plants, is a protein most closely related to AlaDC. To investigate whether the new gene AlaDC originate from gene SDC and to determine the biochemical properties of the two proteins from Camellia sinensis, the sequences of CsAlaDC and CsSDC were analyzed and the two proteins were over-expressed, purified, and characterized. Results The results showed that exon-intron structures of AlaDC and SDC were quite similar and the protein sequences, encoded by the two genes, shared a high similarity of 85.1%, revealing that new gene AlaDC originated from SDC by gene duplication. CsAlaDC and CsSDC catalyzed the decarboxylation of alanine and serine, respectively. CsAlaDC and CsSDC exhibited the optimal activities at 45 °C (pH 8.0) and 40 °C (pH 7.0), respectively. CsAlaDC was stable under 30 °C (pH 7.0) and CsSDC was stable under 40 °C (pH 6.0–8.0). The activities of the two enzymes were greatly enhanced by the presence of pyridoxal-5′-phosphate. The specific activity of CsSDC (30,488 IU/mg) was 8.8-fold higher than that of CsAlaDC (3467 IU/mg). Conclusions Comparing to CsAlaDC, its ancestral enzyme CsSDC exhibited a higher specific activity and a better thermal and pH stability, indicating that CsSDC acquired the optimized function after a longer evolutionary period. The biochemical properties of CsAlaDC might offer reference for theanine industrial production.

scholarly journals Effects of Feed Mixed with Lactic Acid Bacteria and Carbon, Nitrogen, Phosphorus Supplied to the Water on the Growth and Survival Rate of White Leg Shrimp (Penaeus vannamei) Infected with Acute Hepatopancreatic Necrosis Disease Caused by Vibrio parahaemolyticus

Biology ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 280
Author(s):  
Linh Nguyen Thi Truc ◽  
Tuu Nguyen Thanh ◽  
To Tran Thi Hong ◽  
Day Pham Van ◽  
Minh Vo Thi Tuyet ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Survival Rate ◽  
Lactic Acid Bacteria ◽  
Vibrio Parahaemolyticus ◽  
Control Group ◽  
Penaeus Vannamei ◽  
Growth And Survival ◽  
Acute Hepatopancreatic Necrosis Disease ◽  
Nitrogen Phosphorus ◽  
Shrimp Health

This study aimed to evaluate the growth, survival rate, and resistance to acute hepatopancreatic necrosis disease (AHPND) of white leg shrimp (Penaeus vannamei) by using Lactobacillus plantarum, Lactobacillus fermentum, and Pediococcus pentosaceus mixed with feed, and at the same time supplying CNP in a ratio of 15:1:0.1 to the water. As a result, the treatments that shrimp were fed with feed containing lactic acid bacteria (LAB), especially L. plantarum, have increased shrimp growth, total hemocyte cells, granulocyte cells, and hyaline cells significantly (p < 0.05) in comparison to the control group. The supply of CNP to the water has promoted the intensity of V. parahaemolyticus effects on shrimp health and significantly decreased total hemocyte cells, granulocyte cells, and hyaline cells by 30–50% in the period after three days of the challenge, except in L. plantarum treatment, which had only a 20% decrease compared to other treatments. In CNP supplying treatments, the AHPND infected rate and mortality of shrimp were higher than those in other treatments. In summary, the supply of CNP had significantly reduced the shrimp’s immune response and promoted the susceptibility of shrimp to AHPND in both cases of use with and without LAB-containing diets.

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