Review
Microbiology
Victor M. Hernandez, Alejandra Arteaga, Michael F. Dunn
Summary: Arginase in bacteria plays crucial roles in nitrogen metabolism, stress resistance, and pathogenesis by hydrolyzing l-arginine to produce l-ornithine and urea. This review explores the regulation and functions of the arginase pathway, along with characteristics of related arginine catabolic pathways, emphasizing on the diverse physiological functions and biochemical features of arginases in different bacterial species.
FEMS MICROBIOLOGY REVIEWS
(2021)
Article
Clinical Neurology
Nour Elkhateeb, Giorgia Olivieri, Barbara Siri, Stewart Boyd, Karolina M. Stepien, Reena Sharma, Andrew A. M. Morris, Thomas Hartley, Laura Crowther, Stephanie Grunewald, Maureen Cleary, Helen Mundy, Anupam Chakrapani, Robin Lachmann, Elaine Murphy, Saikat Santra, Mari-Liis Uudelepp, Mildrid Yeo, Isaac Bernhardt, Sniya Sudakhar, Alicia Chan, Philippa Mills, Debora Ridout, Paul Gissen, Carlo Dionisi-Vici, Julien Baruteau
Summary: This study aims to characterize epilepsy in argininosuccinic aciduria and correlate it with clinical, biochemical, radiological, and electroencephalographic data. It found that epilepsy is frequent and polymorphic in argininosuccinic aciduria, and is associated with neurodevelopmental comorbidities. Prognostic factors for pharmacoresistance in epilepsy were also identified.
Article
Fisheries
Huan Chen, Zuhao Zhang, Zhihong Wu, Ruibing Peng, Xiamin Jiang, Qingxi Han, Maowang Jiang
Summary: The goal of this study was to explore the detoxification metabolic pathway and regulatory mechanism of the cuttlefish under ammonia nitrogen stress. The study found that the cuttlefish can detoxify ammonia nitrogen into urea through urea metabolism and utilize amino acid metabolic pathways to reduce ammonia nitrogen content in the body. However, these pathways are inhibited under high ammonia nitrogen stress.
Article
Fisheries
Haolong Li, Muzi Zhang, Haibo Jiang, Yuwen Fan, Xue Li, Rixin Wang, Yunxia Qian, Ming Li
Summary: This study found that ammonia poisoning can lead to oxidative damage, immunosuppression, and inflammation in yellow catfish. Arginase may be an important target of ammonia toxicity, and exogenous arginine supplementation can alleviate the symptoms of ammonia poisoning in yellow catfish.
FISH & SHELLFISH IMMUNOLOGY
(2021)
Article
Neurosciences
Xiaofan Yu, Peicong Ge, Yuanren Zhai, Wei Liu, Qian Zhang, Xun Ye, Xingju Liu, Rong Wang, Yan Zhang, Jizong Zhao, Dong Zhang
Summary: This study aimed to investigate the association between plasma urea cycle metabolites and the risk of MMD and its subcategories. The study found that plasma ornithine levels are positively associated with the risk of MMD, while levels of arginine, urea, and global arginine bioavailability ratio (GABR) are inversely related to the risk of MMD. Plasma urea cycle metabolites might serve as potential biomarkers for the risk of MMD.
FRONTIERS IN NEUROSCIENCE
(2023)
Article
Biochemistry & Molecular Biology
J. Lisa Hoogenboom, Marty Kwok-Shing Wong, Susumu Hyodo, W. Gary Anderson
Summary: In this study, the mechanisms of nitrogen movement across the spiral valve of the cloudy catshark were investigated. The molecular identification of two ammonia transporters (Rhp2 and Rhbg) and a urea transporter (UT) revealed their specific cellular localizations. The mRNA abundance of Rhp2 and UT were found to be influenced by fasting and feeding, indicating their involvement in nitrogen homeostasis in the cloudy catshark.
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY
(2023)
Article
Genetics & Heredity
Apolline Imbard, Juliette Bouchereau, Jean-Baptiste Arnoux, Anais Brassier, Manuel Schiff, Claire-Marine Berat, Clement Pontoizeau, Jean-Francois Benoist, Constant Josse, Francois Montestruc, Pascale de Lonlay
Summary: This study retrospectively reviewed the clinical and biological data of patients with urea cycle disorders (UCDs) treated with citrulline and/or arginine. The results highlight the importance of citrulline supplementation in the management of UCDs.
ORPHANET JOURNAL OF RARE DISEASES
(2023)
Article
Physiology
Dexiang Feng, Zhiguo Yang, Ming Li
Summary: This study aimed to investigate the effect of N-carbamylglutamate (NCG) supplementation on ammonia tolerance in yellow catfish. The results showed that NCG supplementation can improve the ammonia tolerance of yellow catfish, and the activation of the urea cycle may be related to the activity of argininosuccinate synthetase (ASS).
FRONTIERS IN PHYSIOLOGY
(2023)
Article
Physiology
Takahiro Hasumura, Keita Kinoshita, Yoshihiko Minegishi, Noriyasu Ota
Summary: This study aimed to investigate the synergistic effect of tea catechins and low-dose ornithine in activating the urea cycle to reduce blood ammonia levels during exercise. The study used hepatocyte-like cells derived from human-induced pluripotent stem (iPS) cells to assess the effect of tea catechins combined with ornithine on urea cycle activity, and also conducted a human pilot study to validate the synergistic improvement in ammonia metabolism by tea catechins in combination with ornithine.
EUROPEAN JOURNAL OF APPLIED PHYSIOLOGY
(2023)
Article
Nutrition & Dietetics
Aleksandra Szlas, Jakub Michal Kurek, Zbigniew Krejpcio
Summary: L-arginine is a safe endogenous amino acid involved in various regulatory functions in the body. It may be helpful in managing disturbed metabolism, regulating blood pressure, and alleviating type 2 diabetes symptoms, but the mechanisms underlying these effects are not fully understood.
Review
Endocrinology & Metabolism
Teresa C. Delgado, Javier de las Heras, Maria L. Martinez-Chantar
Summary: This study indicates that nitrogen metabolism is altered in MAFLD, which may contribute to hepatic ammonia accumulation and the progression of fatty liver disease. The authors suggest that regulating the gut-liver axis nitrogenous balance could be an effective therapeutic approach for treating fatty liver disease.
FRONTIERS IN ENDOCRINOLOGY
(2022)
Article
Environmental Sciences
Xiangjuan Yan, Fei Zhao, Guosheng Wang, Zhen Wang, Mingxi Zhou, Limin Zhang, Guoxiang Wang, Yanshan Chen
Summary: The widespread occurrence of cyanobacteria blooms damages water ecosystem and threatens potable water safety and human health. Exogenous L-lysine significantly inhibits the growth of dominant cyanobacteria Microcystis aeruginosa in freshwater, but the molecular mechanism is unclear. This study investigated the effects of algicide L-lysine using non-target and target metabolomic analysis. The results showed that 8 mg L-1 lysine disrupts amino acid metabolism, particularly arginine and proline metabolism. The study suggests that lysine affects arginine metabolism and ornithine-ammonia cycle to inhibit the growth of M. aeruginosa.
BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY
(2023)
Article
Multidisciplinary Sciences
Richard G. Dorrell, Adrien Villain, Benoit Perez-Lamarque, Guillemette Audren de Kerdrel, Giselle McCallum, Andrew K. Watson, Ouardia Ait-Mohamed, Adriana Alberti, Erwann Corre, Kyle R. Frischkorn, Juan J. Pierella Karlusich, Eric Pelletier, Helene Morlon, Chris Bowler, Guillaume Blanc
Summary: Horizontal gene transfer is an important source of genetic novelty in eukaryotic genomes, particularly in ochrophytes like diatoms. Bacterial HGTs have been identified as the predominant source of recently arrived genes in diatoms, enriching genes encoding secreted proteins and contributing to their evolution. The study provides insights into the frequency, sources, and functional contributions of HGT in algal evolution.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Environmental Sciences
Ruiyu Bi, Xintong Xu, Liping Zhan, Anfeng Chen, Qianqian Zhang, Zhengqin Xiong
Summary: The community structure and abundance of soil ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) were affected by the substitution of chemical fertilizers with organic manure. This substitution significantly reduced the potential of ammonia oxidation and resulted in decreased N2O and NO emissions.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Plant Sciences
Khadim Dawar, Hammad Khan, Mohammad Zaman, Christoph Muller, Syed Sartaj Alam, Shah Fahad, Mona S. Alwahibi, Jawaher Alkahtani, Beena Saeed, Shah Saud, Hafiz Mohkum Hammad, Wajid Nasim
Summary: The application of urea with biochar can significantly reduce NH3 and N2O emissions, as well as promote wheat growth and yield. Nitrapyrin further enhances these effects, indicating its potential for mitigating greenhouse gas emissions and increasing nitrogen use efficiency in agriculture.
JOURNAL OF PLANT GROWTH REGULATION
(2021)
Article
Biochemistry & Molecular Biology
Justin W. J. Chan, Mel Boo, Wai P. Wong, Shit F. Chew, Yuen K. Ip
Summary: The fluted giant clam, Tridacna squamosa, can perform light-enhanced shell formation with the assistance of symbiotic dinoflagellates. This process involves increased Ca2+ transport, absorption of exogenous Ca2+, and regulation of intracellular Ca2+ concentration by SERCA. The expression of SERCA-like transporter in the ctenidium and inner mantle of T. squamosa plays a crucial role in light-enhanced shell formation.
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY
(2021)
Article
Marine & Freshwater Biology
Jeslyn S. T. Poo, Mel V. Boo, Shit F. Chew, Yuen K. Ip
Summary: This study investigated the phototrophic potentials and relative abundances of Symbiodinium, Cladocopium, and Durusdinium in different organs of the giant clam Tridacna squamosa, finding that the symbiont population was dominated by Durusdinium in individuals from Vietnam. The proportions and phototrophic potentials of the three dinoflagellate genera varied among organs and along the outer mantle length, indicating different physiological responses. These results suggest that the association with different genera or species of dinoflagellates may provide distinct physiological advantages to the host clam under varying environmental conditions.
Article
Biochemistry & Molecular Biology
Caryn Z. Pang, Yuen K. Ip, Shit F. Chew
Summary: The marble goby, a freshwater fish, can adapt to survive in seawater and only has one Na+/K+-ATPase alpha-subunit isoform in its gills. During exposure to seawater, the transcript level of Nka alpha 1 significantly increases on day 1 and day 6, while Nka alpha 3 only increases significantly on day 1.
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY
(2021)
Article
Marine & Freshwater Biology
Yuen K. Ip, Mel Boo, Miguel Mies, Shit F. Chew
Summary: The study found that after 30 days of exposure to darkness, giant clams showed significant changes in coloration and gene expression in the outer mantle. However, after returning to a normal photoperiod for just 11 days, the quantity of symbionts and coloration increased significantly, indicating that the giant clam-coccoid dinoflagellate holobiont is phototrophically plastic and particularly tolerant to bleaching.
Article
Biochemistry & Molecular Biology
Mel Boo, Caryn Z. Pang, Shit F. Chew, Yuen K. Ip
Summary: Giant clams require increased transport of Ca2+ and HCO3- for shell formation. This study identified two proteins involved in HCO3- transport and found that their expression levels increased significantly in response to light, suggesting their role in light-enhanced uptake of HCO3-.
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY
(2022)
Article
Environmental Sciences
Caryn Z. Pang, Mel Boo, Yuen K. Ip, Shit F. Chew
Summary: Research on giant clams reveals that dinoflagellates utilize AMT2 to absorb ammonia in photosynthesis, particularly with a stronger absorption capacity in dinoflagellates residing in the outer mantle, enhancing the assimilation process of ammonia.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Genetics & Heredity
Germaine C. Y. Teng, Mel V. Boo, Siew H. Lam, Caryn Z. Pang, Shit F. Chew, Yuen K. Ip
Summary: This study reports on the glycerol transport protein in the symbionts of giant clams and suggests potential differences in glycerol transport capabilities among different genetic types.
Article
Biochemistry & Molecular Biology
Yuen K. Ip, Charmaine W. Q. Leong, Mel Boo, Wai P. Wong, Siew H. Lam, Shit F. Chew
Summary: African lungfishes are highly ammonia-tolerant obligatory air-breathers. The study found that branchial vacuolar-type H+-ATPase (Vha) played a crucial role in regulating the acidification of the external medium in lungfishes. Furthermore, exposure to high ammonia concentrations resulted in increased expression and activity of Vha, enhancing its ability to acidify the external medium.
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Caryn Z. Pang, Yuen K. Ip, Shit F. Chew
Summary: This study used transcript levels of ammonia transporter in different genera of Symbiodiniaceae dinoflagellates to estimate their potential of ammonia transport in the fluted giant clam. The results indicated that different phylotypes of Symbiodinium and Cladocopium have different potentials of ammonia transport, and Symbiodinium phylotypes might have higher potential of NO3- transport than ammonia transport. The study also revealed disparate potentials of ammonia transport among Symbiodiniaceae phylotypes residing in different organs of T. squamosa, suggesting functional diversity among these phylotypes.
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY
(2022)
Article
Marine & Freshwater Biology
Raagavi Mani, Mel Boo, Siow Y. Ng, Shit F. Chew, Yuen K. Ip
Summary: Giant clams harbor symbiotic dinoflagellates that possess their own carbon concentration mechanism and are influenced by light exposure. The study indicates that light enhances the gene and protein expression levels of the symbiotic dinoflagellates in the clam's outer mantle, and different species may vary in their ability to generate CO2.