The annelid phosphagens

Gonyauline: a novel endogenous substance shortening the period of the circadian clock of a unicellular alga

The circadian clock in the unicellular alga Gonyaulax polyedra is accelerated by a substance in extracts from the cells themselves. The extracts have been fractionated using the circadian rhythm of bioluminescence as bioassay. The active substance, termed gonyauline, has been isolated and characterized as a novel low molecular weight cyclopropanecarboxylic acid (S-methyl-cis-2-(methylthio) cyclopropanecarboxylic acid). Synthetic gonyauline has a similar shortening effect on the period of the circadian clock.

Study of phosphagens in two trematodes

Extracts from the adults of two trematodes Fasciola gigantica and Paramphistomum explanatum have been shown to contain three phosphagens, phosphoarginine, phosphocreatine, and phosphoglycocyamine. The three phosphokinases involved in the transphosphorylation of these phosphagens in both worms were inhibited by EDTA and mercuric ions while iodoacetate had no effect.

Comparative studies of vertebrate and invertebrate pyruvate kinases

1. Electrophoretic patterns showed that among the vertebrates studied, L isozyme was present in rat and frog liver and also in rat kidney. 2. M2 is a frequent component in vertebrate tissues, giving support to the proposal that M2 is the ancestral form differentiating to other isozymes. 3. The above trend cannot simply apply to invertebrates. 4. Muscle pyruvate kinases from various animals were inhibited by the particular phosphagen present in their muscle. 5. The inhibition may have an important role in the regulation of glycolysis in muscle.

Distribution of creatine, guanidinoacetate and the enzymes for their biosynthesis in the animal kingdom. Implications for phylogeny

1. The distribution of creatine and the creatine-synthesizing enzymes in the animal kingdom has been investigated. Creatine was found in tissues of all vertebrates examined, and in various invertebrates from phyla Annelida, Echinodermata, Hemichordata and Chordata, subphylum Cephalochordata. The activities of the creatine-synthesizing enzymes, arginine-glycine transamidinase and guanidinoacetate methylpherase, were not detected in the hagfish or in any of the invertebrates, including those in which creatine was found, with the exception that transamidinase activities were detected in the amphioxus and salt water clam; however, these activities are considered to be artifacts for reasons mentioned in the text. Additional evidence that the hagfish and various creatine-containing invertebrates could not synthesize creatine was the observation that these animals did not convert one or the other of the likely precursors of creatine (arginine and glycine) into creatine, in vivo. Further, the inability of these animals to synthesize creatine is correlated with the observations that all animals tested were able to abstract creatine from their aqueous environment. 2. The activities of the creatine-synthesizing enzymes were detected in the sea lamprey and in all but a few of the other vertebrates examined. Neither activity could be detected in the sharks and rays (cartilaginous fish), buffalo fish (bony fish) or the snapping turtle. Transamidinase or guanidinoacetate methylpherase activity could not be found in the salamander or garter snake, respectively. 3. The results obtained with the lamprey are in direct contrast with those obtained with the hagfish (both subphylum Agnatha, class Cyclostomata). The lamprey had the ability to synthesize creatine and did not abstract creatine from lake water. The hagfish did not have any apparent ability to synthesize creatine and did abstract creatine from sea water. The present report thus supports the theory that the myxinoid (hagfish) and petromyzoid (lamprey) agnathans are only distantly related. 4. The lack of creatine-synthesizing enzyme activities in the cartilaginous fishes may have phylogenetic significance, but may also be explained by the availability of creatine in the diet of these animals. The lack of one or both enzyme activities in vertebrates other than the hagfish and the cartilaginous fish is suggested to be the result of creatine in the diet.

Motility and energy-rich phosphorus compounds in spermatozoa of Octopus dofleini martini

The spermatozoa of the giant octopus of the North Pacific, freshly removed from spermatophores, showed very little motility, but on dilution with sea-water or 2.7 % NaCl, followed by dialysis against either of these two media, they became intensely motile and remained so for several days at 2 to 10 °C. At higher temperatures, particularly above 25 °C, octopus spermatozoa lost their motility rapidly. At 35 °C, complete and irreversible loss of motility occurred within less than 1 min. The motility of octopus spermatozoa at 2 to 10 °C persisted under both anaerobic and aerobic conditions and did not require the presence of exogenous glycolysable sugar. The addition of spermatophoric plasma to a motile sperm suspension inhibited motility. Other inhibitors were sodium azide, 2, 4-dinitrophenol and ethylenediaminetetra-acetate, at 0.001 M concentrations. ATP, ADP and arginine phosphate have been identified and quantitatively measured in octopus spermatozoa. On prolonged incubation of motile sperm suspensions a t 3 °C, ATP and ADP did not decline appreciably, whilst arginine phosphate decreased considerably. The decrease was even more pronounced in sperm suspensions which had first been inactivated by short exposure to 35 °C, prior to prolonged incubation at 3 °C. Glycogen, the main carbohydrate store of octopus spermatozoa, remained at a high concentration even in sperm suspensions kept for 5 days at 3 °C, and there was no appreciable difference in that respect between a sample containing motile spermatozoa and one in which, at the outset of incubation, the spermatozoa were immobilized by heating to 35 °C.