Diatoms of some water bodies in northeastern West Siberia. Communication 1. Centrophyceae

In the phytoplankton of northeastern West Siberian water bodies, Bacillariophyta were a dominant group of the 7 most abundant algal divisions, with the occurrence of the members of the class Centrophyceae varying from 27 to 100%. Scanning electron microscopy revealed complete species composition of the class Centrophyceae that dominates the phytoplankton of Lake Delingde, the Delingde and Bol’shaya Kheta rivers (Aulacoseira, 3 species; Cyclostephanos, 1; Cyclotella, 5; Discostella, 1; Melosira, 1; Pliocaenicus, 1; Puncticulata, 1; Stephanodiscus, 6). The phytoplankton of the class Centrophyceae in the Taz River now has a new member, Puncticulata radiosa. New species of the genus Cyclotella in West Siberian algal flora were revealed: C. arctica, C. comensis, and C. vorticosa. The findings helped more precisely define the ranges of the rare taxa and add new diagnostic features to the diagnoses of C. comensis and Stephanodiscus invisitatus.     

Estimation of the carry-over of substances by dragonflies from water bodies to land in the forest-steppe of West Siberia

The results of many years’ monitoring of the number and distribution of dragonflies in the Chany area of the Baraba forest-steppe are presented. An estimation of the biomass carry-over by dragonflies from water bodies to land ecosystems is given. The data presented provide evidence of the important role of dragonflies in the migration of substances from water bodies to land.     

Notes on three algae of small bodies of water

The algae here described are Quadricoccus laevis Fott, Dichotomococcus curvatus Korshikov and Gloeodendron ramosa Korshikov. They were found in Cheshire, England.     

Human evolution in Siberia: from frozen bodies to ancient DNA

Background  

The Yakuts contrast strikingly with other populations from Siberia due to their cattle- and horse-breeding economy as well as their Turkic language. On the basis of ethnological and linguistic criteria as well as population genetic studies, it has been assumed that they originated from South Siberian populations. However, many questions regarding the origins of this intriguing population still need to be clarified (e.g. the precise origin of paternal lineages and the admixture rate with indigenous populations). This study attempts to better understand the origins of the Yakuts by performing genetic analyses on 58 mummified frozen bodies dated from the 15^th to the 19^th century, excavated from Yakutia (Eastern Siberia).     

Karyotypes of some Cypriniform fishes from the water bodies of Armenia

Karyotypes of six species of Cypriniformes from the water bodies of Armenia—blackbrow Acanthalburnus microlepis, white bream Blicca bjoerkna transcaucasica, chub Leuciscus cephalus orientalis, stone moroco Pseudorasbora parva, mursa Barbus mursa, and Angora stone loach Barbatula angorae were studied. The karyotype of A. microlepis is represented by 50 chromosomes (2n = 50), 10M + 28SM + 12STA, NF = 88; of B. bjoerkna transcaucasica, by 2n = 50, 12M + 24SM + 14STA, NF = 86; of L. cephalus orientalis, by 2n = 50, 12M + 18SM + 20STA, NF = 80; of P. parva, by 2n = 50, 8M + 16SM + 26STA, NF = 74; of B. mursa, by 2n = 100, 6M + 36SM + 58STA, NF = 142; and of B. angorae, by 2n = 50, 8M + 24SM + 18STA, NF = 86. The intraspecific and interspecific chromosome polymorphism of species of the genera Blicca, Leuciscus and Pseudorasbora is described.     

Fatty acids of some algae from the Bohai Sea.

The fatty acid compositions of 22 species of marine macrophytes, belonging to the Ceramiales, Cryptonemiales, Nemalionales, Laminariales, Chordariales, Scytosiphonales, Desmarestiales, Dictyosiphonales, Fucales, Dictyotales and Ulvales and collected from the Bohai Sea, were determined by capillary gas chromatography. The contents of polyunsaturated fatty acids (FAs) in the Bohai Sea algae, in comparison with the same species from the Yellow Sea were found to be lower. Red algae had relatively high levels of the acids 16:0, 18:1(n-7), 18:1(n-9), 20:5(n-3) and 20:4(n-6), and those examined were rich in C(20) PUFAs, these chiefly being arachidonic and eicosapentaenoic acids. The major FAs encountered in the Phaeophyta were 14:0, 16:0, 18:1(n-9), 18:2(n-6), 18:3(n-3), 18:4(n-3), 20:4(n-6) and 20:5(n-3). C(18)PUFAs are of greater abundance in the brown algae than in the red algae examined. All three green algae from the Ulvales had similar fatty acid patterns with major components, 16:0, 16:4(n-3), 18:1(n-7), 18:2(n-6), 18:3(n-3), and 18:4(n-3). They contained 16:3(n-3) and more 16:4(n-3), were rich in C(18)PUFAs, chiefly 18:3(n-3) and 18:4(n-3) and had 18:1(n-7)/18:1(n-9) ratios higher than 1.     

Photoproduction of hydrogen from water in hydrogenase-containing algae.

Scenedesmus obliquus and Chlorella vulgaris cells had active hydrogenase after dark anaerobic adaptation. Illumination of these algae with visible light led to an initial production of small quantities of hydrogen gas which soon ceased owing to production of oxygen by photolysis of water. The presence of oxygen-absorbing systems in a separate chamber, not in contact with the algae, gave only a slight stimulation of hydrogen production. Addition of sodium dithionite directly to the algae led to an extensive light-dependent production of hydrogen. This stimulation was due to oxygen removal by dithionite and not to its serving as an electron donor. 3-(3,4-Dichlorophenyl)-1,1-dimethylurea, an inhibitor of photosystem II, abolished all hydrogen photoproduction. Hydrogen evolution was not accompanied by CO₂ production and little difference was noted between autotrophically and heterotrophically grown cells. Hydrogen was not produced in a photosystem II mutant of Scenedesmus even in the presence of dithionite, establishing that water was the source of hydrogen via photosystems II and I. Hydrogen production was stimulated by the presence of glucose and glucose oxidase as an oxygen-absorbing system. Oxygen inhibited hydrogen photoproduction, even if oxygen was undetectable in the gas phase, if the algal solution did not contain an oxygen absorber. It was demonstrated that under these conditions hydrogenase was still active and the inability to produce hydrogen was probably due to oxidation of the coupling electron carrier.     

Comparative analysis of karyotypes of Opisthorchis felineus from West Siberia

Karyotype of the trematode Opisthorchis felineus from two populations of the Ob and the Tom’ rivers basins in the southeast of the West Siberian plain was investigated. Comparative analysis of the relative length and centromere indices of seven chromosomes showed that they are identical to literature data on the chromosome sets of this trematode species from the lower and upper courses of the Irtysh River. The quality of chromosome spreads improved the former knowledge of the karyotype structure of this species, in particular, the 6th and 7th chromosomes.     

Blood parasites of some birds from northeastern Mexico

A total of 196 birds of 31 species from 15 families from northeastern Mexico was examined for blood parasites; 25 birds (12.8%) of 11 species harbored 1 or more species of hematozoans. Species of Haemoproteus accounted for half of the total infections encountered. Leucocytozoon simondi was found in 2 Mexico ducks (Anas diazi) and this represents the first record of the transmission of this parasite in Mexico. The results of this survey were compared with those obtained nearly 50 yr ago from a survey of birds from the same general area; prevalence in both samples was similar, despite the change to a more agricultural environment over this period.     

Miocene snakes from northeastern Kazakhstan: new data on the evolution of snake assemblages in Siberia

Abstract

The Neogene snake fauna from the central and eastern regions of Eurasia is still largely unknown. This paper reports on a unique snake fauna from the late middle Miocene of the Baikadam and Malyi Kalkaman 1 and 2 localities, northeastern Kazakhstan, which represents the best-documented Miocene snake assemblage in Central Asia. Previous studies admitted that snake fauna could be homogeneous over a large part of Eurasia during the Miocene, with the late middle to early late Miocene assemblages similar to snake assemblages that inhabited Europe in the late early and early middle Miocene. This assumption is partially supported by the presence of Texasophis bohemiacus and Coluber cf. hungaricus, as well as vipers of the ‘V. aspis’ complex. However, the presence of taxa which are (1) probably not related to European representatives (‘Colubrinae’ A and B), (2) probably never occurred in Central and Western Europe and (3) are closely related to species recently inhabiting southern Siberia (Elaphe aff. dione, Gloydius sp.) indicates that faunal dissimilarity was relatively high within Eurasia during the late middle Miocene. This assumption is in accordance with studies of small mammal assemblages which show a decreasing homogenity in the Eurasia in the course of the middle Miocene.     

Characterization of DNA components from some colorless algae

The DNA components of five colorless algae were characterized by their buoyant densities in cesium chloride. Two DNA components were detected in Polytoma obtusum and Polytoma uvella. Upon renaturation of the thermally denatured DNA the minor and approx. 15% of the major DNA component returned to their native densities. The buoyant densities of the major and minor DNA of P. obtusum and P. uvella are different from that of the morphologically and biochemically similar green alga Chlamydomonas reinhardtii. A major and a minor DNA component with the same buoyant densities as that of the green alga Euglena were also found in Astasia longa, which is morphologically similar to Euglena. The renaturation of the minor but not the major component was readily detectable by the change in buoyant density. Only one DNA component was detected in Polytomella agilis and Polytomella caeca. After thermal denaturation approx. 5% of each of these DNA components were renatured readily. Based on these data, the possible evolutionary origin of these colorless algae is discussed.     

Discovery of Rhizopogon associated with Larix from northeastern Siberia: Insights into host shift of ectomycorrhizal fungi

Rhizopogon (Boletales) is an ectomycorrhizal fungal genus that exhibits a strong specificity to Pinaceae. This strict association occurs almost exclusively with Pinus and Pseudotsuga, while associations with other genera in Pinaceae are inconclusive. Here, we describe Rhizopogon laricinus sp. nov. associated with Larix cajanderi distributed in northeastern Siberia, where forest fires are frequent. We confirmed the host identity by comparing rDNA internal transcribed spacer (ITS) sequences obtained from basidiomata and ectomycorrhizal root tips collected at the same sites. Morphological characteristics and molecular identification revealed that R. laricinus is a new species associated with Larix unequivocally. The molecular phylogeny based on ITS sequences placed this species sister to the subgenus Roseoli, which is specific to Pinus, and not to the Pseudotsuga-specific subgenus Villosuli. Thus, R. laricinus evolution does not correspond to host phylogeny as Larix and Pseudotsuga form a monophyletic clade. Instead, ecological traits of Rhizopogon for adapting to disturbed habitats may have driven the host shift to Larix under high-frequency fire ecosystems.     

Restriction Analysis of N-Acetyltransferase 2 Gene in Caucasian Population of West Siberia

Restriction analysis of the NAT2 gene was carried out in inhabitants of Novosibirsk. Polymorphism of this gene for nine known point mutations was studied in a sample of Novosibirsk residents consisting of 109 healthy Caucasians. The frequencies of these mutations did not significantly differ from the frequencies reported for Caucasian populations of other countries. In 79 patients with lung cancer, a region of the NAT2 gene that includes 29.7% of the coding sequence was analyzed for the new mutations by the RFLP analysis. No new mutations were found in this group.     

Restriction analysis of N-acetyltransferase 2 gene in Caucasian population of West Siberia

Restriction analysis of the NAT2 gene was carried out in inhabitants of Novosibirsk. Polymorphism of this gene for nine known point mutations was studied in a sample of Novosibirsk residents consisting of 109 healthy Caucasians. The frequencies of these mutations did not significantly differ from the frequencies reported for Caucasian populations of other countries. In 79 patients with lung cancer, a region of the NAT2 gene that includes 29.7% of the coding sequence was analyzed for the new mutations by the RFLP analysis. No new mutations were found in this group.