摘要:

SYNOPSIS.Stomatogenesis or new mouth formationsensu latorepnts an explicit example of a major morphogenetic phenomenon le life cycle of most ciliate Protozoa. Investigations of the process a number of approaches may yield data of considerable value. The present paper 3 such approaches are treated in some detail.udies of stomatogenesis can be of importance in providing addial information of significance on the structure and physiology a given organism. Five major types or categories of stomatoesis in ciliates are recognized. These are defined and discussed. search related to such an intrinsic value of the phenomenon the K carried out is generally only descriptive, and the most importechnic employed is some method of silver impregnation.a comparative approach is used, then attention may be focused possible homolegies in stomatogenesis as it occurs in diverse ies of ciliates. Such data are (or potentially are) of value not in the practical taxonomy of the organisms involved but also onsideration of phylogenetic and evolutionary interrelationships ing the higher groups comprising the entire subphylum Ciliophora. Such application of comparative studies may well become a very fruitful approach to certain problems in ciliate phylogeny; 2 examples are discussed briefly. Silver impregnation technics are again indispensable.Perhaps stomatogenesis will prove most valuable in the hands of developmental biologists who are seeking to solve 2 of the most intriguing problems in cell biology today: the exact origin of new kinetosomes (or centrioles), and their precise morphogenetic role in the life cycle of a cell or unicellular organism. Since this third approach to the study of stomatogenesis is of necessity a dynamic one, the researcher must employ sophisticated experimental technics to obtain data at the molecular and macromolecular levels of both organization and function. Some progress in this area has already been made, but the availability of “ideal” organisms has perhaps not been as widely realized as it should. Certain of the “higher” ciliates have a mode of stomatogenesis which would lend itself beautifully to fruitful investigation of problems concerning both replication or neoformation of kinetosomes and their possible role in fibrillogenesis in unicellular or

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1967.tb01436.x

出版商:Blackwell Publishing Ltd    

年代:1967

数据来源: WILEY

摘要:

SYNOPSIS.Culture forms of 9 species of Trypanosomatidae were studied. Of these,Crithidia fasciculata, Leishmania brasiliensis, L. donovani, L. tropica, Trypanosoma conorhini, T. cruziandT. rangeliconsumed significantly less glycerol than glucose, both when the 2 substrates were offered singly or simultaneously. On the other hand,T. gambienseandT. rhodesienseconsumed as much glycerol as glucose when the 2 substrates were given separately. When both substrates were offered simultaneously, more glycerol than glucose was consumed, but the sum of glucose + glycerol carbon taken up approximated closely that taken from glucose alone. This held for species consuming only little glycerol, indicating that in all cases some mutual inhibition took place. Atttempts to adaptT. cruzito glycerol consumption were unsuccessful. WhenT. gambienseandT. rhosiensewere cultivated in the presence of glycerol, their normrapid glycerol consumption remained also unchanged but, curiothey consumed more glucose than before “adaptation.” Iodoacetami and NaF strongly inhibited glucose and glycerol absorption of 7gambiense; phloridzin, deoxygalactose and deoxyglucose gave nonificant inhibition. KCN slightly stimulated glucose absorption, weakly inhibited glycerol absorption. Omission of sodium from medium was without effect, while lack of CO2markedly inhiglucose and glycerol uptake. Galactose was not a satisfactory sub strate forT. gambienseandT. rhodesiense, nor were deoxygalactos and deoxyglucose. These 3 hexoses were consumed in small amonly and did not allow maintenance of motil

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1967.tb01437.x

出版商:Blackwell Publishing Ltd    

年代:1967

数据来源: WILEY

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1967.tb01438.x

出版商:Blackwell Publishing Ltd    

年代:1967

数据来源: WILEY

摘要:

SYNOPSIS.Vitamin B12, biotin and thiamine requirements of 10 strains ofVolvulina steiniiand 1 strain ofV. pringsheimiiwere studied. Vitamin B12is required for growth of both species, thiamine stimulates growth slightly, and biotin has no discernible effect on growth. The minimum concentration of vitamin B12giving a growth response inV. steinii, strain SC‐2, was 10−8g/ml, and maximum growth response was obtained with 1.1 × 10−7g/ml.An organic carbon source is required for growth ofV. steiniibut not ofV. pringsheimii.Growth ofV. steinii, strain SC‐2, occurred in 20 of 21 carbon sources tested. Optimal growth with each carbon source was largely dependent upon pH. Except for pyruvate, acetate, and ethanol, carbon source utilization was light‐dependent, and growth in ethanol was reduced in the dark.Isocitric lyase activity was detected inV. steiniigrown on acet

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1967.tb01439.x

出版商:Blackwell Publishing Ltd    

年代:1967

数据来源: WILEY

摘要:

SYNOPSIS.During logarithmic growth,Colpidium campylumproduced a complex, heat‐stable material which elevated the reproductive ate ofTetrahymenasubsequently inoculated into the culture. This material stimulated only early stages in the growth ofTetrahymena—effect accompanied by an increased number and size of food vacuoles. TheColpidiumproduct was found to be RNA, precipitable from the medium by acetone. Lipids and proteins or peptides were also present in the complex; these appeared to protect the RNA from the action of chemical and physical age

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1967.tb01440.x

出版商:Blackwell Publishing Ltd    

年代:1967

数据来源: WILEY

摘要:

SYNOPSIS.The physiologic response ofTetrahymena pyriformisW to glucose, as measured by the respiratory rate in a buffered suspension, was found to be altered by exposure of the culture to this carbohydrate in the peptone‐based growth medium. Glucose‐grown cells had an elevated respiratory rate in the presence of glucose in the Tris‐buffered suspension, while cells not grown with the glucose supplement required sodium and potassium for the response. Orthophosphate elevated the rate of oxygen consumption independently of the glucose effect. The endogenous respiratory of glucose and non‐glucose cultured cells were significantly diffe The 2 types of cells responded differently to the cations, sod and potassium, and were not identical in sensitivity to iodoacet Iodoacetate poisoning was found to be due to inhibition of “uncompetitive” type, potentiated by glucose, orthophosphate, the absence o

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1967.tb01441.x

出版商:Blackwell Publishing Ltd    

年代:1967

数据来源: WILEY

摘要:

SYNOPSIS.We have undertaken the study of intracellular parasites which probably constitute one of the stadia of the development of a coccidium:Myriosporides amphiglenae.This study, carried out by means of optical microscopy as well as electron microscopy, has allowed the observation of close similarities withPlasmodium, Lankesterella, Eimeria, ToxoplasmaandSarcocystis.The wall consists of 3 membranes and has a micropore. Besides classical cytoplasmic inclusions (mitochondria, Golgi system, ergastoplasm and vacuoles), various tubular forms fill the anterior third of the cell, in which about twenty hollow peripheral fibrils are also observed.

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1967.tb01442.x

出版商:Blackwell Publishing Ltd    

年代:1967

数据来源: WILEY

摘要:

SYNOPSIS.Acriflavin concentrations of 0.025 μg/ml and higher were LoLeptomonas karyophilusin NNN medium to which no ribohad been added, and did not bring about the production of dys plastic forms. Upon addition of 0.4 μg/ml of riboflavin, contions of acriflavin up to 10.0 μg/ml allowed growth and rein the production of up to 86% dyskinetoplastic forms. Under conditions, increasing concentrations of acriflavin decreased the growth rate while increasing the rate of production of dyskinetoplastic forms. The number of dyskinetoplastic forms increased with time while the number of kinetoplastic forms remained approximately constant or decreased due to death. At a concentration of 1.0 μg/ml acriflavin and 0.4 μg/ml riboflavin, growth was primarily due to the production of dyskinetoplastic f

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1967.tb01443.x

出版商:Blackwell Publishing Ltd    

年代:1967

数据来源: WILEY

摘要:

SYNOPSIS.The pathogenicity for mice and cell culture, and the growth ratesin vitroof two strains ofTritrichomonas foetuswere compared. A new strain ofT. foetus (T. foetus“G”) which was isoated less than a year before use in the experiments described, was more pathogenic to mice but had a longer generation time than an old strain (T. foetus“M”). The old strain has been maintainedin vitrofor over five years. The characteristics observed for the strains ofT. foetusexamined resembled those ofT. vaginalisrather thanT. gallinae.In strains of the latter species there is a good correlation between growth rate and pathog

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1967.tb01444.x

出版商:Blackwell Publishing Ltd    

年代:1967

数据来源: WILEY

摘要:

SYNOPSIS.Out of 64 nutrients tested, none replaced glycerol for growth in the dark ofPrymnesium parvum.Some metabolites enahanced growth in the light, and in the presence of glycerol also in the clark. Good growth with glycerol could be obtained in the absence of CO2. Survival of cultures in the dark in media without glycerol was prolonged by various nutrients. Thioglycerol in glycerol‐containing media inhibited growth in light and darkness. ApparentlyPrymnesium parvumhas a specific glycerol requirement for dark growt

ISSN:0022-3921    

DOI:10.1111/j.1550-7408.1967.tb01445.x

出版商:Blackwell Publishing Ltd    

年代:1967

数据来源: WILEY