Studies of oligosaccharide linkages by simultaneous determination of component aldehydes in dialdehyde fragments as (2,4-dinitrophenyl)hydrazones

The component aldehydes in dialdehyde fragments formed by periodate oxidation of oligosaccharides were converted quantitatively into the corresponding (2,4-dinitrophenyl)hydrazones by the simple procedure of treatment with excess (2,4-dinitrophenyl)hydrazine hydrochloride in 1,2-dimethoxyethane. Then, by chromatographic separation of the hydrazones on a small column of silica gel and subsequent spectrophotometric analysis, it was possible to determine the position of glycosidic substitution in μmolar amounts of various types of glucobioses, oligosaccharides of senega, and some synthetic (1→6)-β-D-gluco-oligosaccharides.     

Activation of mouse splenic lymphocyte guanylate cyclase by calcium ion.

The guanosine 3',5'-cyclic monophosphate (cGMP) level in the mouse splenic lymphocytes was increased about 2- to 3-fold by concanavalin A. This increase was completely dependent on the presence of Ca2+ in the medium. Homogenates of mouse splenic lymphocytes contained significant guanylate cyclase [EC 4.6.1.2] activity in both the 105,000 X g (60 min) particulate and supernatant fractions and both fractions required Mn2+ for full activity. Calcium ion (3mM) activated soluble guanylate cyclase 3-fold at a relatively low concentration of Mn2+ (less than 1mM) but inhibited the particulate enzyme slightly at all Mn2+ concentrations tested. Concanavalin A itself did not stimulate either fraction of guanylate cyclase. Thus these results suggest that elevation of the cGMP level in lymphocytes by concanavalin A might be brought about by stimulation of Ca2+ uptake and activation of soluble guanylate cyclase by the latter.     

Selective degradation of altered tomato β-fructofuranosidase molecules by neutral protease

Evidence is presented for the selective breakdown of altered tomato β-fructofuranosidase molecules by a neutral protease from Bacillus subtilis.     

Isolation and Characterization of a Filamentous Phage,Vf33, Specific for Vibrio parahaemolyticus

Phage Vf33, a filamentous phage about 1,400 nm long and 7 nm wide, specific for Vibrio parahaemolyticus, was isolated and characterized. The buoyant density of Vf33 in CsCl was 1.292 g/cm³. As with other filamentous phages, the lytic activity of Vf33 was resistant to heating below 80 C and to treatment with diethylether, acetone or methanol but sensitive to chloroform. The nucleic acid of this phage is single-stranded circular DNA 8.4 kb in size. The viral genome was converted to a double-stranded replicative form in the host cell. Among the strains tested, only V. parahaemolyticus strains possessing K38 antigen was sensitive to the phage.     

Plasma normetanephrine: A biochemical marker of sympathetic nerve function in man

The concentration of the catecholamines in plasma are regarded by many investigators as biochemical markers of sympathoadrenal activity in man. This study was designed to: 1) assess the relationship of normetanephrine (NMN), the metabolite of norepinephrine (NE) most likely to represent degration of newly synthesized and released “active” norepinephrine, to that of norepinephrine in plasma of normal volunteers and 2) to determine regional variations in plasma normetanephrine concentrations at venous and arterial sites of patients undergoing cardiac catherization. The findings suggest that 1) plasma normetanephrine reflects sympathoadrenal activity and neurotransmitter production at both peripheral neuronal and adrenal medullary sites and 2) there is net removal of normetanephrine by liver and kidney. Plasma normetanephrine should provide assistance in the biochemical assessment of sympathoadrenal tone in man and in patients with various autonomic disorders.     

Some observations on the fine structure of the mantis shrimp heart

Summary The electron microscopic structure of the myocardium of the mantis shrimp is descriped. Particular attention is paid to the organization of the nerve terminal and the sarcotubular system. The general appearance of this myocardium is characterized by deep invagination of the plasma membrane at the level of Z-band and large irregular shaped mitochondria. It possesses a very well developed sarcotubular system, consisting of the longitudinal system and two transverse elements making two sets of contact to each other. One forms dyad and the other forms triad at the level of M- and Z-band, respectively. The organization of the myoneural junction in this muscle is very simple and undifferentiated. In general, a special structural differentiation is invariably observed at both sides of the contact area. In spite of the fact that synaptic vesicles and a differentiated membrane are found at the naked process of this cardiac nerve, specialization such as subsynaptic fold formation has not been observed at the muscle side which is in contact with the nerve process. Observations made on the sarcotubular system and the nerve termination have been discussed with reference to their physiological significance. This investigation was supported by the Public Health Service Research Grants HE 06968-04 and NB 03348-04 of the National Institutes of Health, Bethesda, and the U. S. Department of the Army through its Far East Research Office.     

Redescription of Lepadichthys coccinotaenia Regan 1921 and description of Lepadichthys trishula sp. nov. from southern Japan (Gobiesocidae: Diademichthyinae)

Ichthyological Research - Lepadichthys coccinotaenia Regan 1921 (Gobiesocidae: Diademichthyinae) is redescribed on the basis of 60 specimens, including the holotype, and a new species of...     

Integrative genomic phylogeography reveals signs of mitonuclear incompatibility in a natural hybrid goby population

Hybridization between divergent lineages generates new allelic combinations. One mechanism that can hinder the formation of hybrid populations is mitonuclear incompatibility, that is, dysfunctional interactions between proteins encoded in the nuclear and mitochondrial genomes (mitogenomes) of diverged lineages. Theoretically, selective pressure due to mitonuclear incompatibility can affect genotypes in a hybrid population in which nuclear genomes and mitogenomes from divergent lineages admix. To directly and thoroughly observe this key process, we de novo sequenced the 747‐Mb genome of the coastal goby, Chaenogobius annularis, and investigated its integrative genomic phylogeographics using RNA‐sequencing, RAD‐sequencing, genome resequencing, whole mitogenome sequencing, amplicon sequencing, and small RNA‐sequencing. Chaenogobius annularis populations have been geographically separated into Pacific Ocean (PO) and Sea of Japan (SJ) lineages by past isolation events around the Japanese archipelago. Despite the divergence history and potential mitonuclear incompatibility between these lineages, the mitogenomes of the PO and SJ lineages have coexisted for generations in a hybrid population on the Sanriku Coast. Our analyses revealed accumulation of nonsynonymous substitutions in the PO‐lineage mitogenomes, including two convergent substitutions, as well as signals of mitochondrial lineage‐specific selection on mitochondria‐related nuclear genes. Finally, our data implied that a microRNA gene was involved in resolving mitonuclear incompatibility. Our integrative genomic phylogeographic approach revealed that mitonuclear incompatibility can affect genome evolution in a natural hybrid population.     

Composition of uterine milk and its changes with gestational period in red stingrays (Hemitrygon akajei)

Uterine milk is secreted in the uterus for embryo nutrition in several elasmobranch species and may contribute to rapid embryonic growth, but the details of its composition and its functions are poorly understood. In this study, to explore the roles of uterine milk for embryos, its components throughout the gestational period were analysed in detail. Uterine milk was collected from pregnant red stingrays (Hemitrygon akajei) in the early, middle and late gestational periods, respectively (n= 3 for each period). The crude composition, constituent proteins and fatty acids in the milk were analysed. The uterine milk was rich in proteins throughout the gestational period, whereas lipids dramatically increased in the middle period and reduced slightly towards the late period. Some proteins potentially associated with nutrition, cartilage growth and embryonic immunity were found. Several enzymes related to central metabolism were also detected. The constituent fatty acids in the middle and late periods were similar to those in the egg yolks of elasmobranchs, except for C18:2, which was rich only in the uterine milk. The most abundant fatty acid in the milk was C16:1, which could function as a lipokine to promote lipid metabolism in the embryo. This study's data suggest that uterine milk may be secreted in addition to the egg yolk in elasmobranchs to support rapid and healthy embryonic growth.