Purification and stability of octameric mitochondrial creatine kinase isoform from herring (Clupea harengus) organ of vision

Tissue and plasma enzyme activities and chemical analytes in Golden Trevally from a public aquarium

OBJECTIVE

Veterinary care of aquatic species, particularly fish, is limited by a lack of knowledge regarding their unique physiology. Tissue enzyme activities measured in plasma are used for assessing function and potential damage to specific organs and tracking disease progression in live animals. The objective of this study was to identify tissue(s) of origin and plasma concentrations for specific enzymes in healthy Golden Trevally Gnathanodon speciosus. We hypothesized that enzymes would exhibit tissue-specific tropisms, with higher activities in one or more tissues compared to others.

METHODS

Six fish were randomly selected from a public aquarium population to obtain antemortem blood samples. The fish were then euthanized, and tissue samples were collected via gross necropsy. Six enzyme activities and two chemical analytes were examined across samples of plasma and 10 tissues from each fish.

RESULT

Enzyme activities exhibited significant organ specificities. Aspartate aminotransferase, lactate dehydrogenase, and creatine kinase levels were highest in skeletal muscle, with variably high levels in gonads. Alkaline phosphatase levels were highest in the kidney, spleen, and liver. Alanine aminotransferase levels had high specificity for the liver. Gamma-glutamyl transferase was only detectable in the kidney and plasma.

CONCLUSION

This work establishes baseline tissue enzyme origins for Golden Trevally, which will aid clinicians in diagnostic interpretation of blood chemistries and improve veterinary care for this understudied fish species.

Natural Products Containing 'Rare' Organophosphorus Functional Groups

Phosphorous-containing molecules are essential constituents of all living cells. While the phosphate functional group is very common in small molecule natural products, nucleic acids, and as chemical modification in protein and peptides, phosphorous can form P⁻N (phosphoramidate), P⁻S (phosphorothioate), and P⁻C (e.g., phosphonate and phosphinate) linkages. While rare, these moieties play critical roles in many processes and in all forms of life. In this review we thoroughly categorize P⁻N, P⁻S, and P⁻C natural organophosphorus compounds. Information on biological source, biological activity, and biosynthesis is included, if known. This review also summarizes the role of phosphorylation on unusual amino acids in proteins (N- and S-phosphorylation) and reviews the natural phosphorothioate (P⁻S) and phosphoramidate (P⁻N) modifications of DNA and nucleotides with an emphasis on their role in the metabolism of the cell. We challenge the commonly held notion that nonphosphate organophosphorus functional groups are an oddity of biochemistry, with no central role in the metabolism of the cell. We postulate that the extent of utilization of some phosphorus groups by life, especially those containing P⁻N bonds, is likely severely underestimated and has been largely overlooked, mainly due to the technological limitations in their detection and analysis.