Weitere biologische Literatur (eingeschränkter Zugriff)
[Chapter 2:] Biogenesis of the cell wall and other glycoconjugates of Mycobacterium tuberculosis
Marcelo E. Guerin
Patrick J. Brennan
- The re-emergence of tuberculosis in its present-day manifestations - single, multiple and extensive drug-resistant forms and as HIV-TB coinfections - has resulted in renewed research on fundamental questions such as the nature of the organism itself, Mycobacterium tuberculosis, the molecular basis of its pathogenesis, definition of the immunological response in animal models and humans, and development of new intervention strategies such as vaccines and drugs. Foremost among these developments has been the precise chemical definition of the complex and distinctive cell wall of M. tuberculosis, elucidation of the relevant pathways and underlying genetics responsible for the synthesis of the hallmark moieties of the tubercle bacillus such as the mycolic acid-arabinogalactan-peptidoglycan complex, the phthiocerol- and trehalose-containing effector lipids, the phosphatidylinositol-containing mannosides, lipomannosides and lipoarabinomannosides, major immunomodulators, and others. In this review, the laboratory personnel who have been the focal point of some to these developments review recent progress towards a comprehensive understanding of the basic physiology and functions of the cell wall of M. tuberculosis.
A catalogue of the geophilomorph centipedes (Chilopoda) from Central and South America including Mexico
Luis Alberto Pereira
- This paper is an annotated catalogue of the geophilomorph centipedes known from Mexico, Central America, West Indies, South America and the adjacent islands. 310 species and 4 subspecies in 91 genera in 111 families are listed, not including 6 additional taxa of uncertain generic identity and 4 undescribed species provisionally listed as 'n.sp.' under their respective genera. Sixteen new combinations are proposed: Garrina pujola (CHAMBERLIN, 1943) and G. vera (CHAMBERLIN, 1943), both from Pycnona; Nesidiphilus plusiopol'us (ATTEMS, 1947), from Mesogeophilus VERHOEFF, 1901; Polycricus bredini (CRABILL, 1960), P. cordoballensis (VERHOEFF, 1934), P. hailiensis (CHAMBERLIN, 1915) and P. nesiotes (CHAMBERLIN, 1915), all from Lestophilus; Tuoba baeckstroemi (VERHOEFF, 1924), from Geophilus (Nesogeophilus); T. culebrae (SILVESTRI, 1908), from Geophilus; T. laticollis (ATTEMS, 1903), from Geophilus (Nesogeophilus); Titanophilus hasei (VERHOEFF, 1938), from Notiphilides (Venezuelides); T. incus (CHAMBERLIN, 1941), from Incorya; Schendylops nealotus (CHAMBERLIN, 1950), from Nesondyla nealota; Diplethmus porosus (ATTEMS, 1947), from Cyclorya porosa; Chomatobius craterus (CHAMBERLIN, 1944) and Cil. orizabae (CHAMBERLIN, 1944), both from Gosiphilus. The new replacement name Schizonampa Iibera is proposed pro Schizonampa prognatha (CRABILL, 1964) ex Schizotaellia prognatha CRABILL, 1964 nec Schizotaenia prognatha COOK, 1896. Keywords: Neotropics, Chilopoda, Geophilomorpha, list of species, new combinations, new replacement name.
A check-list of the Greek macrofungi including hosts and biogeographic distribution : 1. Basidiomycotina
- As a preliminary step towards a more intensive research on the diversity of macromycetes in Greece, an updated check-list of the Greek mycoflora is presented together with information on the host-substrates and geographic occurrence. The data originated from a thorough literature search and the authors' field observations. In total, 58 families, 214 genera and 811 species of fungi are recorded belonging to Basidiomycetes. The systematics and nomenclature of the relative bibliography have been updated and suitably revised. The large gaps in our knowledge on the existence and distribution of higher fungi in Greece are emphasized.
A collection of Frullania from Papua New Guinea
A comparative study of the myrmicine sting apparatus (Hymenoptera, Formicidae)
- The morphology of the skeletal portions of the sting apparatus is described and compared in 63 genera of myrmicine ants in order to evaluate its taxonomic potential in this difficult subfamily. The survey covers about half of the myrmicine genera, and an but 3 small tribes (Ochetomyrmecini, Melissotarsini, Stegomyrmicini). Interspecific variation in the apparatus is described in a third of the genera examined. In addition, the sting apparatus of the primitive ponerine ant, Amblyopone pallipes is described for comparison with the primitive myrmicines; and the sting associated glands (poison gland, Dufour's gland) are illustrated for single species of Amblyopone, Basiceros, Monomorium, Aphaenogaster, Crematogasier, and Zacryptocerus.
A comparative study of the symbiotic relationship between beetles of the genus Cremastocheilus (Coleoptera: Scarabaeidae) and their host ants (Hymenoptera: Formicidae)
Gary Duane Alpert
- The North Arnerican species of the genus Cremastocheilus are reviewed. These belong to 5 subgenera, Macropodina, Trinodea, Anatinodia, Mymcotonus, and Cremastocheilus. Taxonomie changes are: She inclusion of Crernastocheilus nitens and C. chapini in the subgenus Cremastocheilus rather than Myrmecotonus. Also Anatinodia is elevated to subgeneric status. A key to the subgenera is provided, as is a key to the species of the 5 subgenera, recognizing that the 35 species in the subgenus Cremastocheilus are in need of revision. A critical review of the host records, geographic distribution, and ecology of the Tribe Crernastocheilini (Family Scarabaeidae. subfamily Cetoniinae) is provided. This contains enormous numbers of new records for both the genera Genuchinus and CremastocheiLus both from the literature and from the extensive field work that is reported here for the first time. A Summary of the host records is presented in tabular form. This table shows the association of all species of Cremastocheilus with ants as adults and the larvae either associated with the vegetable material of the ant nests or with vegetable material in rodent burrows. Genuchinus is shown to be a general predator on soft bodied insects while the other genera of the Cremastocheilini are associated with plants, particularly bromeliads. A detailed study of the external morphology and sexual dimorphism of the genera Genuchinus and Crernastocheilus is presented. All species of Cremastocheilus can be sexed with the naked eye by the difference in the shapes of the abdominal terminal Segments, wherein males have the posterior border of the last ventral abdominal segment either straight or slightly bowed, while females have this border broadly rounded. There are other microscopic sexual differences in the structure of the legs. The rest of the external morphology is also presented, particularly from the point of view of adaptations to either a predaceous or rnyrmecophilous existente. Particularly adapted for predation are the pointed maxillae which are used for piercing prey. Particularly adapted for myrmecophily are the mentum, the maxillae, the generally thick exoskeleton, trichomes on both the anterior and posterior angles of the pronotum, the elytra, and the legs (which are adapted to the nest substrate of the host ant nests. Exocrine glands are described for Genuchinus ineptus and at least 1 species of each of the 5 subgenera of Cremastocheilus. In general, there are no gland cells nor glandular areas in Genuchinuc that are comparable to those of Cremastocheilus. The gland cells and glandular areas are quite extensive andvariable arnong species of Cremastocheilus. The frontal gland of some Cremastocheilus (strongly developed in C. castaneus and the C. canaliculatus species group, but weakly developed in the C. wheeleri species group) is described for the first time. Because these glands are not found in Genuchinus ineptuc, a species with general predatory habits, it is thought that these play a role, as yet unknown, in interactions with ants. The life cycles of the subgenera of Cremastocheilus are described. The general life cycle entails adult beetles eclosing in ant nests during the summer and then undertaking dispersal flights. The adults then enter ant nests and ovenivinter there, eating ant larvae during the Winter. Another dispersal flight occurs in the spring during which the adults mate and enter ant nests again. The females then lay eggs and the adults die. The eggs hatch and the larvae spend 3 instars feeding upon vegetable material in the nests. The lmae then pupate in typical scarabaeine earthen cells made of fecal material and soil. These eclose in the summer and the cycle is repeated. Variation from species to species is largely in the timing. Leaving the nest in late Summer, mating seems to be triggered by rainfall in all the species studied. Mating of C. (Macropodina) beameri takes place in rodent burrows. Males seem attracted to females from a distance but the mechanism of this remains obscure. In the subgenus Trinodia, mating takes place on sandy washes or roadsides where females land. In the subgenus Myrmecotonus, maüng also takes place in sandy areas. In C. (Cremastocheilus) mating takes place on sand bars along rivers in the southeastern U.S. and in sand dunes in northeastern U.S. The femaies dig down into the sand. Males locate these places by some unknown mechanism and then dig down to copulate with the females. Field experiments showed unequivocaily that males dig only into areas occupied by females. No sex-specific Sex attractant glands have been located in females so far. Dispersal to ant nests occurs after mating except for C. (Macropodina) beameri which lays its eggs in the rodent burrows and then probably disperses to ant nests. Beetle activity going in and out of nests was studied using wire hardware cloth screens over entrances to Mynnecocystus nests. The mesh size was such that the ants could move freely in or out but the beetles got stuck by their thoraces. The direction then could be interpreted by the direction in which they got stuck. By this method, C. stathamae was shown to leave nests from 23 June to 1 September with a peak on 6 July, just after the beginning of the summer rains. Beetles entered nests from June 23 to August 3, however 39% entered on July 16, probably pulsed by the leaving time which was correlated with the rains. Life cycle timing: C. (Macropodina) develop in the nests of Wood rats (Neotoma sp.]. Females lay about 40 eggs each. The 3 larval instars to pupation take about 1 month. Pupae are found from late August to weil into September. In other subgenera as well, larvae are found in parts of the nest devoid of ants, The timing is similar in all the subgenera found with ants. Mortality factors: While ants attack Cremastocheilus adults, there is no evidence that they are ever killed by ants nor is there evidence that ants kill larvae nor hard earthen pupae cases which protect the pupae. During dispersal fiights and mating, the adults are exposed to predation and evidence is presented that shows predation by horned toads, spiders, magpies, and tiger beetles. Probably most mortality occurs in the larval and pupd stages where the beetles are attacked by internal parasites and fungus. Further rnortality is caused by limitation of the food supply during the larval stage. Reentering nests: Females of C. (Macropodina) beameri select specific rodent and other burrows, attract males for rnating. and then enter the burrow for oviposition. C. stathamae are carried into the ants nests from as far away as 25ft. The beetles appear to land spontaneously after flying randomly over M. depilis nesting areas. Then the wander about waiting for the ants to carry them into the nests. Cremastocheilus hirsutus fly low over the ground searching for Pogonomyrrnex barbatus nests, land. and move straight for the nest entrances which they enter unhindered. Among all species, the ants frequently eject beetles but the net rnovement is in. Ants frequently attacked Cremastocheilus in laboratory observation nests when they were introduced. These attacks seldom resulted in the death of the beetles and the beetles were eventually ignored. When the beetles entered brood chambers, where they fed upon larvae, they were mostly ignored and even licked assiduously by the ants. A principle defensive behavior by the beetles is feigning death (letisimulation). The beetles give off an unpleasant "dead fish odor when collected in the I field. Experiments show that this substance functions to fend off some predators but further experiments indicated that these substances were ineffective against both ants and kangaroo rats. Experiments with various species of Cremastocheilus adults indicate that the adults eat only ant larvae. The beetles will eat larvae of non-host ants but show preferences for the larvae of their normal hosts. Under the same experimental conditions. Genuchinus ineptus adults will feed on a variety of insect adults and larvae. Field experiments on the function of trichome secretions did not indicate that they function to attract ants at a distance nor are they involved in worker acceptance. Laboratory experiments in which areas with a high concentration of gland cells were presented to ants showed that no ants were attracted. Laboratory introduction of Cremastocheilus hamisii adults into Fomica schau.si nests yielded many interactions including ants licking the anterior pronotal angles, the mentum area where the frontal glands empty and a carina over the eye with a dense pad of short setae. These are areas of concentration of gland cells and these are the first observations of licking by ants in specific sites containing exocrine glands. Radioisotope experiments showed food exchange among ants but never from ants to beetles. Other experiments showed that ants can pick up radioactivity from the beetles without feeding on trichome secretions. Evolutionary pathways: Adult Cremastocheilini probably followed the evolutionary route from adult predation on soft bodied insects to specialized feeding upon ant brood and the subsequent development of the beetle larvae in vegetable material in the ant colonies. Thus Genuchininseptus makes a logical outgroup in that they are general predators probably feeding mostly on Diptera larvae associated with Sotol plants in the field. The rnajor evolutionary step taken by Cremastocheiluswas to specialize on ant brood. Then the species radiated into ant colonies inhabiting southwestem North Arnenca. Most of the ant hosts invaded have quantities of vegetable material in their nests sufficient to support several developing scarab larvae. Host colonies are large, contain accessible brood, and are usually dominant foragers Evidence supports the idea that the species of Cremastocheilus have differentes in behavior and morphology that reflect adaptation to the behavioral ecology of different species of ants rather than different evolutionary levels of integration into ant colonies.
A contribution to the theoretical analysis of the schooling behavior of fishes
Albert Eide Parr
A disease of rabbits characterized by a large mononuclear leucocytosis, caused by a hitherto undescribed bacillus Bacterium monocytogenes (n. sp.)
Everitt George Dunne Murray
Robert Alexander Webb
Meredith Blake Robson Swann
- 1. In investigating a spontaneous epidemic disease of rabbits, a micro-organism was isolated in pure cultures which reproduced the characteristic lesions of the natural disease.
2. The bacteriological characters of this bacillus are described and the impossibility of identifying it with previously recorded organisms justifies its being considered a new species. The name Bacterium monocytogenes is proposed.
3. Animal passage raised "virulence" when the doses were well chosen, and increased virulence accentuated the production of necrotic lesions. Overwhelming doses of culture resulted in lowering of "virulence" by animal passage.
4. Bacterium monocytogenes, in doses less than the M.L.D., produced in the circulating blood of rabbits an extreme monocytosis. The responses of the other white cells. were either transient or inconstant.
5. Repeated doses of the organism became progressively less effective as stimuli to large mononuclear production.
6. The cell content of the thoracic duct did not reflect the high degree of monocytosis in the circulating blood.
7. On intrapleural injection of peptone broth and B. coli, the cells of the resultant exudate were primarily polymorphonuclears, even though the circulating blood showed a high monocytosis. With intrapleural injection of B. monocytogenes, when the blood stream was rich in large mononuclears, a pleural exudate containing 30 per cent of these cells was obtained.
8. Phagocytosis experiments in vitro showed that the large mononuclears, while they phagocyted B. coli indifferently, took up B. monocytogenes with an avidity in all respects equal to that of the polymorphonuclear neutrophiles.
A monograph of the burmanniaceae
Fredrik Pieter Jonker
- The present publication is intended to be a monograph on the family of Burmanniaceae. It is divided into three parts: General Part, Critical Part and Taxonomical Part. The first part, General Part, contains general remarks on the taxonomy, distribution and use of the family. The second part, Critical Part, contains general and geobotanical remarks on the genera of the family, whereas the third part, the Taxonomical Part, gives the determination keys to the tribes, subtribes, genera, sections, subsections and species, the description of these groups with literature, distribution and the indications of the types. New varieties, species and larger groups are described in the taxonomical part in foot-notes.
A monograph on the genus Cystoderma
Alexander Hanchett Smith