scholarly journals Responses to freezing exposure of hatchling turtles Trachemys scripta elegans: factors influencing the development of freeze tolerance by reptiles

1992 ◽  
Vol 167 (1) ◽  
pp. 221-233 ◽  
Author(s):  
T. A. Churchill ◽  
K. B. Storey
Keyword(s):  
Amino Acid Content ◽  
Freeze Tolerance ◽  
Cold Climate ◽  
Free Amino Acid Content ◽  
Survival Times ◽  
Painted Turtles ◽  
Factors Influencing ◽  
Oxygen Sensitive ◽  
Ice Content ◽  
Total Body

Hatchling red-eared turtles Trachemys (= Pseudemys) scripta elegans (Wied) from a Louisiana population display a significant ability to withstand the freezing of extracellular body fluids. All animals survived at least 2 h of freezing at −2.5 or −4 degrees C. At −2.5 degrees C, survival declined to 50% after 6 h of freezing and no animals recovered after 24 h or longer, when mean ice content reached 54.7 +/− 1.4% of total body water. At −4 degrees C, all turtles recovered from 4 h of freezing exposure with a mean ice content of 49.6 +/− 2.4%, but survival dropped sharply thereafter with no animals recovering after 8 h, when ice content had reached 64.5 +/− 0.7%. Survival times were substantially shorter and percentage ice values greater than comparable values for hatchling painted turtles (Chrysemys picta (Schneider)) from northern populations subjected to identical freezing exposures. The ability to synthesize cryoprotectants in response to freezing was poorly developed in T. s. elegans; maximal accumulation of glucose was only 3.2 mumol g-1 wet mass in liver. Lactate content increased two- to threefold in oxygen-sensitive organs (heart and brain) during freezing, but levels of lactate and other putative cryoprotectants were unchanged in other organs. Total free amino acid content rose significantly in liver, muscle and blood during freezing; increased taurine concentration was primarily responsible for the changes in liver and blood. The capacity for freezing survival by T. s. elegans hatchlings from southern populations would be of limited use for hibernation in a cold climate, but the metabolic responses to freezing displayed by these animals might be enhanced by northern populations to increase their freeze tolerance.

Natural freezing survival by painted turtles Chrysemys picta marginata and C. picta bellii

1992 ◽  
Vol 262 (3) ◽  
pp. R530-R537 ◽  
Author(s):  
T. A. Churchill ◽  
K. B. Storey
Keyword(s):  
Freeze Tolerance ◽  
Chrysemys Picta ◽  
Painted Turtle ◽  
Survival Times ◽  
Painted Turtles ◽  
Ice Content ◽  
Total Body ◽  
Natural Freezing ◽  
Free Amino Acid Pools ◽  
Continuous Freezing

Hatchlings of both the Midland (Chrysemys picta marginata) and Western (C. picta bellii) subspecies of the painted turtle tolerate the freezing of extracellular body fluids while overwintering in terrestrial nests. Fall-collected hatchlings survived 3 days of continuous freezing at -2.5 degrees C, with ice contents of 43.5 +/- 1.0% of total body water (SE; n = 24) for C. picta marginata and 46.5 +/- 0.8% (n = 32) for C. picta bellii. Survival times dropped to 4-5 h when temperature was lowered to -4 degrees C, correlated with ice contents of greater than or equal to 50%. However, C. picta marginata tested immediately after excavation from nests in the spring showed greater freeze tolerance, with survival extending to 11 days at -2.5 degrees C and a higher mean ice content of 50.2 +/- 1.2% (n = 6). Spring hatchlings also had high supercooling points, -1.07 +/- 0.13 degrees C (n = 8), that dropped within 3 days to -4.83 +/- 0.83 degrees C (n = 4), suggesting a breakdown of endogenous ice-nucleating agents when hibernation ended. A search for possible cryoprotectants showed that both subspecies accumulated glucose and lactate in liver during freezing (net increase = 3-13 mumols/g wet wt); both also maintained large free amino acid pools in organs, with taurine making up 21-47% of the total.

Adaptations of metabolism for freeze tolerance in the gray tree frog, Hyla versicolor

1985 ◽  
Vol 63 (1) ◽  
pp. 49-54 ◽  
Author(s):  
Janet M. Storey ◽  
Kenneth B. Storey
Keyword(s):  
Energy Charge ◽  
Freeze Tolerance ◽  
Creatine Phosphate ◽  
Hyla Versicolor ◽  
Tree Frog ◽  
Mature Adult ◽  
Cryoprotectant Synthesis ◽  
Ice Content ◽  
Total Body ◽  
Gray Tree Frog

Biochemical adaptations allowing the natural survival of extracellular freezing were examined in the gray tree frog, Hyla versicolor. Laboratory-reared immature adults froze between −1 and −1.5 °C and survived 5 days of freezing at −2 °C as well as repeated rapid bouts of freeze–thaw. Measurements of ice content showed 41.5% of total body water frozen. Glycerol accumulated as the cryoprotectant in sexually mature adult H. versicolor (423 μmol/mL in blood) while both glycerol and glucose accumulated in immature adults (16.3 ± 6.8 and 25.9 ± 11.6 μmol/mL in blood, respectively). Cryoprotectant synthesis was freezing stimulated only and did not occur over long-term cold acclimation at 0 to 1 °C. Cryoprotectant synthesis was correlated with a 203% increase in liver total phosphorylase activity and an increase in phosphorylase a content from 40 to 60%. Activities of 15 other enzymes of intermediary metabolism were determined in liver and leg muscle; activities of most enzymes increased with freezing exposure as did soluble protein content. Survival of freezing depends upon anaerobic mechanisms of energy production in tissues. Frogs frozen at −2 °C accumulated lactate in liver and muscle. Energy charge dropped in both tissues and the creatine phosphate reserves of muscle were depleted.

Evaluation of seed amino acid content and its correlation network analysis in wild soybean (Glycine soja) germplasm in Japan

2021 ◽  
Vol 19 (1) ◽  
pp. 35-43
Author(s):  
Awatsaya Chotekajorn ◽  
Takuyu Hashiguchi ◽  
Masatsugu Hashiguchi ◽  
Hidenori Tanaka ◽  
Ryo Akashi
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Free Amino Acid ◽  
Acid Content ◽  
Free Amino ◽  
Glycine Soja ◽  
Wild Soybean ◽  
Amino Acid Content ◽  
Soybean Seeds ◽  
Free Amino Acid Content

AbstractWild soybean (Glycine soja) is a valuable genetic resource for soybean improvement. Seed composition profiles provide beneficial information for the effective conservation and utilization of wild soybeans. Therefore, this study aimed to assess the variation in free amino acid abundance in the seeds of wild soybean germplasm collected in Japan. The free amino acid content in the seeds from 316 accessions of wild soybean ranged from 0.965 to 5.987 mg/g seed dry weight (DW), representing a 6.2-fold difference. Three amino acids had the highest coefficient of variation (CV): asparagine (1.15), histidine (0.95) and glutamine (0.94). Arginine (0.775 mg/g DW) was the predominant amino acid in wild soybean seeds, whereas the least abundant seed amino acid was glutamine (0.008 mg/g DW). A correlation network revealed significant positive relationships among most amino acids. Wild soybean seeds from different regions of origin had significantly different levels of several amino acids. In addition, a significant correlation between latitude and longitude of the collection sites and the total free amino acid content of seeds was observed. Our study reports diverse phenotypic data on the free amino acid content in seeds of wild soybean resources collected from throughout Japan. This information will be useful in conservation programmes for Japanese wild soybean and for the selection of accessions with favourable characteristics in future legume crop improvement efforts.

Effect of lead stress on the growth and metabolism of Eruca sativa M. seedlings

2005 ◽  
Vol 53 (3) ◽  
pp. 319-327 ◽  
Author(s):  
F. A. Faheed
Keyword(s):  
Seed Germination ◽  
Root Length ◽  
Dry Matter ◽  
Lead Concentration ◽  
Amino Acid Content ◽  
Proline Content ◽  
Growth Inhibitors ◽  
Eruca Sativa ◽  
Free Amino Acid Content ◽  
Harmful Effects

Among the toxic elements, lead has great importance because of its harmful effects on animal and human health. Heavy metals are known as growth inhibitors and consequently exhibit toxicity symptoms in plants. The effect of different concentrations of lead on seed germination, seedling growth and some metabolites of Eruca sativa plants was examined. The percentage of seed germination gradually decreased with an increase in the lead concentration. A considerable reduction in fresh and dry matter as well as shoot and root length was obtained as a result of increasing lead concentration. Among these parameters, total root length was a more sensitive parameter than shoot length at every lead concentration. The proline content increased, in most cases, with increasing lead concentration. The same trend was observed for the free amino acid content. Soluble protein generally increased with an increase in lead concentration. In contrast, the total protein gradually decreased as the lead concentration increased, particularly at the highest levels used.

scholarly journals Free amino acid content in muscle tissue of bighead carp and wels catfish

2016 ◽  
Vol 72 (10) ◽  
pp. 632-636 ◽  
Author(s):  
Renata Pyz-Łukasik ◽  
Maria Szpetnar ◽  
Waldemar Paszkiewicz ◽  
Marcin R. Tatara ◽  
Adam Brodzki
Keyword(s):  
Amino Acid ◽  
Free Amino Acid ◽  
Muscle Tissue ◽  
Acid Content ◽  
Free Amino ◽  
Amino Acid Content ◽  
Bighead Carp ◽  
Predatory Fish ◽  
Free Amino Acid Content ◽  
Natural Diet

The present research was aimed at a comparative analysis of free amino acid (FAA) levels in the muscle tissue of herbivorous and predatory fish. The FAA concentration in the muscle tissue samples from bighead carp and wels catfish was determined by ion-exchange chromatography. The bighead carp muscle tissue, as compared to that of wels catfish, showed significantly higher concentrations of arginine, histidine, methionine, phenyloalanine, alanine, asparagine, serine, glycine, and taurine, but significantly lower levels of isoleucine, leucine, threonine, valine, glutamine, cystationine, β-alanine, ethanoloamine, as well as aspartic, glutamic, cysteic, α- and γ-aminobutyric acids. The muscle tissues of bighead carp and wels catfish did not differ significantly in the levels of cystine, lysine, tryptophan, tyrosine, α-aminoadipic acid, cytrulline, ornithine and 1-methyl-histidine. Proline was detected only in the wels catfish muscle. The results obtained have shown differences in free amino acid concentration in muscle tissue of examined fish. A differentiated natural diet induces changes in free amino acid content in fish tissues. Knowledge of levels of free amino acids which are precursors for biogenic amines facilitates setting the safety criteria for fish and fishery products from species other than those mentioned in the Commission Regulation No 2073/2005

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