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The spermatozoa of Octopus dofleini martini produce anaerobically D(-)-lactic acid and possess a very active D(-)-lactate dehydrogenase. In this respect, while resembling certain microorganisms, they differ strikingly from mammalian spermatozoa which produce L(+)-lactic acid and contain L(+)-lactate dehydrogenase.

At each of five loci in 829 Escherichia coli clones from 156 samples from diverse natural sources, electrophoretic analysis reveals a prominent mobility class (frequency over 0.70) and 2 to 11 distinct mobility classes at lower frequencies. The frequency distribution of the classes argues against the importance of neutral mutations in allozymic variation. Heterosis is not the universal cause of genic polymorphism.

Monomeric ribonuclease A has very low activity toward typically double-stranded RNA's; the dimeric form of ribonuclease A obtained by cross linking the enzyme by dimethyl suberimidate has more than 78 times the activity of the monomer toward polyadenylate . polyuridylate and 440 times the activity of the monomer toward the double-stranded RNA of a virus from Penicillium chrysogenum. The half-life of the dimer in the bloodstream of the rat is 12 times that of the mononmer.

Blood samples from northern elephant seals (Mirounga angustirostris), representing five breeding colonies in California and Mexico, were surveyed electrophoretically for protein variation reflecting underlying genetic differences. No polymorphisms were found among 21 proteins encoded by 24 loci. This uniform homozygosity may be a consequence of fixation of alleles brought about by the decimation of this species by sealers in the last century.

Hepatitis-associated antigen can be detected within 2 hours by using an electrophoretic technique and cellulose acetate membranes saturated with antibody. The speed of the technique now allows testing of blood intended for transfusion on the day of collection, and the sensitivity of the method compares favorably with standard immunodiffusion.

The venom proteins of honey bee, Polistes wasp, yellow hornet, and yellow jacket are similar but not identical. Extracts of venom sacs and whole insects contain several proteins not found in the pure venoms.

The nucleotide sequence of " denaturable"leucine acceptor transfer RNA (tRNA(Leu)(3)) from baker's yeast was determined on (32)P-labeled material. The molecule is 85 nucleotides long and can be folded into the "cloverleaf" model for secondary structure. The basis on which the sequence was deduced from the products of complete enzymatic digestion, prior to its unambiguous determination, is presented.

The cationic, antibacterial proteins of polymorphonuclear leukocytes are associated with a unique subcellular particle that is separable through zonal density gradient centrifugation from acid phosphatase-containing particles as well as from particles that contain alkaline phosphatase and lysozyme. Normal macrophages, macrophages stimulated by bacillus Calmette-Guérin, and liver cells lack this particle and the associated group of cationic proteins. Particles physically and biochemically similar to slower sedimenting enzyme-rich particles of polymorphonuclear leukocytes are shared by all the tlhree cell types.

Aggregates were formed when clear supernatants from hepatic microsomes that had been treated with steapsin were desalted and concentrated. These aggregates contain large numbers of uniform tubular elements. These structures resemble microtubules seen in many cells but differ in their substructure. The aggregates were rich in cytochrome P-420. Unlike soluble cytochrome P-420, the cytochrome P-420 contained in the aggregates combines with drugs to give the characteristic difference spectra normally seen only with cytochrome P-450 contained in intact microsomes.

Two electrophoretic vari ants of leucine aminopeptidase show direct association with two genetically controlled forms of alkaline phosphatase. Treatment of plasma with neuraminidase converted the faster-migrating form of both enzymes to slower-moving forms, but plasmas with slowermigrating forms were unaffected by this treatment. The two forms of the enzymes may be due to the presence or absence of a single gene controlling the attachment of sialic acid to the enzyme molecules.

In cultures of mouse adrenocortical tumor cells (Sato's minimal deviation Y-1 clonal strain), the acceleration of steroid biosynthesis after exposure to adrenocorticotropic hormone or cyclic adenosine 3',5'-monophosphate is maximum within 15 to 60 minutes and precedes any significant increase in labeling of protein with [4,5-(3)H]leucine. However, when cytosol proteins are separated by acrylamidegel electrophoresis, rapid changes in the amount and labeling of several protein fractions are evident in less than 30 minutes and are no longer evident within 60 minutes. This finding supports the proposal that the effects of tropic hormones and their intracellular mediators involve rapid selective effects on protein synthesis.

Alkaline hydrolyzates of RNA made in vivo by Escherichia coli contain ribonucleoside-3'-monophosphate-5'-triphosphates. These probably arise by hydrolysis of the initial nucleoside triphosphate from the 5' terminus of the nascent RNA chains. Logarithmically growing cultures, labeled for 45 seconds with (32)P-labeled phosphate, yield about 2000 molecules of labeled tetraphosphate per cell, this yield increasing only slightly with continued labeling. Only the tetraphosphates of adenosine and guanosine have been found in Escherichia coli, and these two are present in approximately equal amounts.

Soluble fractions of human intestinal cancer and fetal intestinal cell membranes produced delayed hypersensitivity reactions in patients with intestinal cancer. These soluble fractions and perchloric acid extracts of intestinal cancer cells were fractionated by polacrylamide-gel electrophoresis. The Gold carcinoembryonic antigen was found in a region of the gels different from that of the skin reactive antigen.

The observation of a cloud-free vortex in the top of a violent convective storm over Oklahoma suggests a mechanism whereby large quantities of air may be brought directly from the lower stratosphere to the lower troposphere in the central part of such storms. That this mechanism, in combination with the torrential rains frequently generated by these systems, is capable of producing radioactive "hot spots" on the ground is pointed out. Climatological considerations and observations of accumulated strontium-90 in soils support the hypothesis that the Plains States are peculiarly subject to heavy contamination compared to other middle-latitude areas because of this mechanism.

Although postsynaptic inhibition of Renshaw cells in the spine is blocked by strychnine the depression of these neurons by electrophoretically administered noradrenaline is resistant to this alkaloid. This finding raises doubts as to whether noradrenaline is an inhibitory transmitter in the spinal cord of the cat.

Of 1200 individuals screened, four had variant erythrocyte lactate dehydrogenases. Three of these, identical electrophoretically to the Mem-1 described by Kraus and Neely, were heterozygous variants involving the a-locus. The fourth, involving the b-locus, appears to be the first example in man of a homozygous variant.

The fibroblasts derived from the skin of a woman heterozygous for an X-linked deficiency of phosphoglycerate kinase represented a mosaic. Two of 22 clones with normal glucose-6-phosphate dehydrogenase activity and hypoxanthine(guanine) phosphoribosyltransferase activity had no phosphoglycerate kinase activity detected by electrophoresis. Because the loci for glucose-6-phosphate dehydrogeniase and hypoxanthine(guanine)phosphoribosyltransferase are already known to undergo inactivation and to be on the short arm of the X chromosome and the locus for phosphoglycerate kinase is on the long arm, these observations support the conclusion that the entire human X chromosome can be involved in X inactivation.

Heterozygosity occurs at the lactate dehydrogenase b-locus in two diploid parthenogenetic species of Cnemidophorus. Each such species produces two different B subunits, one of which is also found in two sexual species and in two triploid parthenogenetic species; the other occurs also in a third sexual species. Interspecific hybridization between sexual species carrying different b-alleles and producing different B subunits may be responsible for the heterozygosity at the lactate dehydrogenase b-locus in diploid parthenogenetic Cnemidophours.

By means of microclectrophoresis in agar gel, we studied the hemolymph proteins of different species of the family Triatomidae (class Insecta) and different species of the families Ixodidae and Argasidae (clalss Arachnoidea). The results show a specific electrophoretic pattern for each species. Insects infected with pathogenic organisms have the same pattern as normal insects.

Heart extracts from over 100 species of birds were subjected to starch-gel electrophoresis at pH 7. The "supernatant" form of malate dehydrogenase, an enzyme present in every extract, was then located on the gels by a specific staining method. The mobility of this enzyme shows very little interspecific variation. Nearly all birds tested have a supernatant malate dehydrogenase that moves as fast as the chicken enzyme. Those species with an enzyme of unusual mobility are of taxonomic interest. For example, hummingbirds and swifts, which are usually considered as two suborders of Apodiformes, are unique among the birds tested in having an enzyme that moves 63 percent as fast as the chicken enzyme. This finding appears to confirm the unity of the Apodiformes, an order whose unity has long been open to question. Similarly all families tested in the shorebird order (Charadriiformes) are unique in having an enzyme that moves 55 percent as fast as the chicken enzyme. The unity of this order was also previously open to question.

Three patterns of 6-phosphogluconic dehydrogenase activity were obtained by starch-gel electrophoresis of blood from domestic cats. Genetic analysis indicates control of these patterns by a pair of alleles at an autosomal locus. Presence of three enzymatically active bands in heterozygotes and of single bands in homozygotes is compatible with at least a dimeric structure for the enzyme.

Two or possibly three isozymes of the enzyme, xanthine dehydrogenase, have been detected in wildtype Drosophila melanogaster. by starchgel electrophoresis. Two genes, rosy and maroon-like, may control these isozymes by producing two different polypeptides that assemble in groups of three or four.

Development of a rapid and sensitive radioassay has permitted study of the conversion of tryptophan to 5-hydroxytryptophan in mammalian tissues. Of normal tissues examined, beef and rat pineal gland contained the highest activity. This is the first direct demonstration of tryptophan hydroxylase in this hydroxyindole-rich tissue. Rat and rabbit brainstem and human carcinoid tumor also had quantities of enzyme that could be measured easily. The reaction requires a reduced pteridine and oxygen and is inhibired by Para-Chorophenylalanine.

The study of genetic regulatory mechanisms operating in plants and animals is of paramount importance in contemporary biology. A precise understanding of the mechanisms that underlie normal cellular differentiation is a prerequisite for understanding neoplastic transformation and genetic disease. At present, we are not aware of a single assay system that can give answers to all questions we are already able to pose. Studies of RNA synthesis are valuable because they provide a direct measurement of transcriptional activity. But these studies remain incomplete until we succeed in unraveling the metabolic roles of the molecules whose synthesis we study. In this respect, the study of enzyme synthesis represents a better defined assay system, although the interpretation of observed fluctuations in synthetic rates is made difficult by the many steps that intervene between the genes and their finished protein products. We propose that a combination of protein biosynthetic and cytogenetic analysis is a promising assay system for further investigation.

Starch-gel electrophoresis of plasina reveals two mnutually exclusive forms of alkaline phosphatase. Analysis of the plasma of 931 birds from 96 sib families of two inbred lines through two generations shows that the faster-moving isozymne is determined by an autosomal gene Ap(2) which is completely dominant to its allele Ap(4) determining the slower form.

Starch-gel electrophoresis of extracts of human liver revealed the presence of a new hexose-6-phosphate dehydrogenase that was slower-moving at pH 8.6 than the sex-linked glucose-6-phosphate dehydrogenase. When the gel plate was stained, galactose-6-phos phate being used as a substrate, this enzyme band stained intensely, but the sex-linked glucose-6-phosphate dehydro genase failed to stain. This new human enzyme may well be homologous with the autosomally inherited glucose-6-phosphate dehydrogenase of the deer mouse (Peromyscus maniculatus), re ported by Shaw and Barto.

Two acid phosphatases were demonstrable by polyacrylamide gel electrophoresis. They had different mobilities and different heat stabilities in 1.0M acetate buffer, pH 5.2. Both phosphatases had the same electro-phoretic mobility in tris buffer at pH 7.5, gave one boundary in the analytical ultracentrifuge in tris or acetate buffer, and had the same sedimentation coefficient. The difference in these properties suggests an alteration in conformation of the proteins by the buffer systems.

HeLa cells arrested in metaphase synthesized relatively normal amounts of mitochondrial RNA, while little RNA synthesis associated with the nucleus was detected. The RNA synthesized resembled the portion of mitochondrial RNA sensitive to ethidium bromide in interphase cells, with major peaks at 21, 12, and 4S. Unlike that in interphase cells, RNA synthesis in the mitoclhonidrial fraction of mitotic cells was completely inhibited by ethidium bromide.

Escherichia coli cells, grown in the presence of chloramphenicol, synthesize a low molecular weight RNA (CM-5S RNA) not bound to ribosomes which is similar to ribosomal 5S RNA. Oligonucleotide patterns derived from ribonuclease digests of 5S RNA and of CM-5S RNA are indistinguishable except that the 5'-terminal oligonucleotides differ. Whereas the nucleotide sequence of the 5'-terminus of normal 5S RNA is (p)U(p)G-, there are three alternate sequences of the 5'-terminus of CM-5S RNA: (p)U(p)U(p)G-, (p)U(p)U(p)U(p)G-, and (p)A(p)U(p)U(p)U(p)G-.

Four variants of human erythrocyte lactate dehydrogenase (LDH) are described. One of these is similar to the one previously described by Boyer and is interpreted as a variant of LDH-B. The other three are thought to represent variants of LDH-A. Studies of families indicate that LDH-A and LDH-B are under separate genetic control and are inherited as autosomal co-dominants. Evidence is presented that the LDH-A locus is not closely linked to the loci for the ABH and Duffy blood group systems.

A genetically determined variant of lactic dehydrogenase has been observed in the red cells of four members of two generations of a Brazilian family. The appearance of the variant after starch-gel electrophoresis of the hemolysates supports the concept that the lactic dehydrogenase isozymes are determined by the interaction of two subunits which are under separate genetic control. The products of the mutant and normal allele do not, however, appear to associate randomly to form isozymes. The similarity of the relative retardation of normal and mutant isozymes in gels made with increasing concentrations of starch suggests that they do not differ significantly in size.

A new method of starch-gel electrophoresis using a technique of staining dependent on enzyme activity has been employed to demonstrate the isozymes of aldolase from a variety of human, rat, and frog tissues. Five of these isozymes were detected in man, seven in the rat, and at least four in the frog. The abilities of these isozymes to cleave fructose-1 ,6-diphosphate and fructose-1-phosphate were compared.

Immunoglobulin A (gammaA) myeloma proteins secreted by plasma-cell tumors of mice are of two types, a common four-chain molecule and a rare two-chain (3.9S) molecule. The close similarity between two-chain gammaA molecules and four-chain gammaA molecules and their polymers is demonstrated in tryptic peptide maps of isolated polypeptide chains and by precipitin reactions with rabbit antiserums to gammaA immzunoglobulins. However, a difference between these two types is distinguishable with homologous antiserums. Homologous antiserums to two-chain gammaA immunoglobulins are specific and do not cross-react with four-chain gammaA immutnoglobulins.

Uteri of pregnant and nonpregnant women contain enzymic activities which inactivate oxytocin. A potent enzyme, which has been partially purified from uterine homogenates, cleaves the prolyl-leucyl peptide bond of oxytocin. This findinig associates for the first time the release of the dipeptide leucylglycinamide with the degradation of neurohypophyseal hormones.

Incorporation of radioactive leucine into electrophoretically separated proteins from mouse tail epidermis indicates that synthesis of alkaline phosphatase is stimulated by vitamin A. It is suggested that some of the diverse effects of vitamin A may be the result of alkaline phosphatase induction.

Electrophoretic resolution of lactate dehydrogenase in mature testes from a variety of animals revealed one or more unusual isozymes in addition to the usual five forms. Dissociation of the enzyme and recombination of the polypeptide subunits led to the formation of new isozymes and to a redistribution of activity among those normally present, indicating that lactate dehydrogenase synthesis in postpubertal testis is controlled by more than two genes.

Peafowl, like other vertebrates, contain multiple forms of lactate dehydrogenase. The electrophoretic properties of the peafowl isoenzymes are unusual in that the isoenzyme from heart tissue can be either more or less anodic than that of muscle, depending on the pH. This finding focuses attention on the problem of isoenzyme identification. It is suggested that isoenzymes be identified on the basis of properties that are chemically and biologically more significant than electrophoretic mobility.

Slow- and fast-migrating electrophoretic variants of human erythrocyte catalase were encountered in four of approximately 200 families. Tests for nine genetic polymorphisms provided evidence suggesting linkage only in the case of the haptoglobin system.

The malate dehydrogenase isoenzymes from the mitochondria of chicken hearts have been partially resolved into separate pools. Reversible denaturation, in concentrated guanidine hydrochloride, does not change the isoenzyme distribution in each pool. This result suggests that the electrophoretic differences among the isoenzymes are not solely conformational in origin.

Ammonium persulfate, a common polymerizing agent for acrylamide gels, can inactivate yeast enolase and produce increased electrophoretic heterogeneity during disc electrophoresis in gels containing 8M urea. The use of riboflavin and light for polymerization or thioglycolate for removal of the persulfate are feasible alternatives.

Two forms of glucose-6-phosphate dehydrogenase, A and B, have been reported in deer mouse tis sues. The B enzyme, which showed autosomally controlled polymorphism, is now found to be equally active to ward glucose-6-phosphate and galac tQse-6- phosphate; the A enzyme is specific for the former. Human and horse livers also have two forms of glucose-6-phosphate dehydrogenase which exhibit the same substrate spe cifities as those in the deer mouse. A wide variety of electrophoretic patterns was seen in the human galactose-active enzyme.

An abnormal fetal hemoglobin, designated hemoglobin F(Texas), was found in the cord blood of five Negro infants (all related and three of them siblings) and of one Caucasian infant. Studies on the chemical structure of this variant indicate that there is a substitution of a lysyl residue for either the fifth or sixth glutamyl residue of the gamma-chain.

A method is described which implements the direct comparison of serum samples from different individuals by simultaneous electrophoresis followed by simultaneous diffusion and precipitation by anti-human horse serum. Results have been evaluated, with an arbitrary reference grid, by comparison of the numbers of precipitin bands present in the paired immunoelectrophoretograms Graphic representation of these differences distinguishes serum samples of like from those of unlike origin.