Organelle membrane fusion: a novel function for the syntaxin homolog Ufe1p in ER membrane fusion.

The fusion of endoplasmic reticulum (ER) membranes in yeast does not require Sec18p/NSF and Sec17p, two proteins needed for docking of vesicles with their target membrane. Instead, ER membranes require a NSF-related ATPase, Cdc48p. Since both vesicular and organelle fusion events use related ATPases, we investigated whether both fusion events are also SNARE mediated. We present evidence that the fusion of ER membranes requires Ufe1p, a t-SNARE that localizes to the ER, but no known v-SNAREs. We propose that the Ufe1 protein acts in the dual capacity of an organelle membrane fusion-associated SNARE by undergoing direct t-t-SNARE and Cdc48p interactions during organelle membrane fusion as well as a t-SNARE for vesicular traffic.

Progress in taxonomy of the Apicomplexan protozoa.

In 1987, 4516 species and 339 genera of the phylum Apicomplexa had been named. They consisted of the gregarines (subclass Gregarinasida) (1624 named species and 231 named genera), the hemogregarines (family Haemogregarinidae) (399 species and 4 genera), the eimeriorins (order Eimeriorida) (1771 species and 43 genera), the hemospororids (order Haemospororida) (444 species and 9 genera), the piroplasmids (order Piroplasmorida) (173 species and 20 genera), and a few others (105 species and 32 genera). The first apicomplexan protozoon was seen by Antony van Leeuwenhoek; in 1674 he saw oocysts of Eimeria stiedai in the gall bladder of a rabbit. The first member of the phylum to be named (by Dufour in 1828) was Gregarina ovata in earwigs. During the quarter century 1826-1850, 41 species and 6 genera of Apicomplexa were named. These numbers increased progressively. In the quarter century 1951-1975, 1873 new species and 83 new genera were named. Data are given for the numbers of named species and genera of apicomplexan protozoa of each group known in 1850, 1875, 1900, 1925, 1950, 1975, and 1987.

Cross-transmission of Eimeria spp. (Protozoa, Apicomplexa) of rodents--a review.

A total of 169 cross-transmission attempts has been made with 44 (11.8%) of the 372 named species of Eimeria of rodents. Of these, 161 were rodent-to-rodent, 6 rodent-to-lagomorph, and 1 each rodent-to-carnivore and rodent-to-bird. None of the last three categories was successful. In the rodent-to-rodent combinations, 39 (80%) of the 49 attempts to transmit a coccidian species from one rodent species to another of the same genus were successful, and only 14 (12.5%) of the 112 attempts to transmit a coccidium to a rodent of a different genus were successful. Eight of the successful attempts were with E. chinchillae, which was the only truly euryxenous species of Eimeria in the group. Two successful attempts were between between the closely related rodent genera Spermophilus and Cynomys, and two were both of E. separata from Rattus norvegicus to some genetic strains but not to others of Mus musculus. One attempt with E. vermiformis from Mus musculus to Rattus norvegicus required treatment of the rat with the immunosuppressant dexamethasone to succeed. More cross-transmission studies are needed to determine the host spectra of the species of Eimeria and other coccidian genera, and to determine the roles of genetics and immunosuppression in their transmission.

The number of species of rodent coccidia and of other protozoa.

About 447 species of coccidia have been named from the 1687 living, known species of rodents; 207 host species, 92 host genera, and 15 host families are represented; this is about 12% of the known species of rodents. About 4600 species of apicomplexan protozoa have been named. Assuming that the same proportion of the total number of apicomplexan species has been named as of the coccidian species, there must actually be about 38,333 species of apicomplexan protozoa. There are 5.4 times as many protozoan genera as of apicomplexan genera. Assuming that the number of species in each genus is the same for all the protozoa as it is for the Apicomplexa, there may actually be 206,998 species of protozoa. This may be too conservative an estimate. Based on other criteria, an estimate of over 20 million species could be made.

Corrections in the names of rodent coccidia (Apicomplexa, Coccidiasina).

The following new taxonomic combinations are introduced for coccidia whose names were previously given erroneously: Dorisa bengalensis (Bandyopadhyay & Ray, 1982) n. comb. from the Indian palm squirrel Funambulus pennanti in India; Eimeria sicistae from the intestine of the birch mouse Sicista tianschanica in the USSR; E. hydrochaeri Carini, 1937 emend. from the capybara Hydrochaerus hydrochaerus in South America; Frenkelia sp. (Doby, Jeannes & Rault 1965) from the brain of the water vole Arvicola sapidus in Europe; Frenkelia sp. (Karstad, 1963) from the brain of the muskrat Ondatra zibethica in North America; Frenkelia sp. (Enemar, 1965) from the brain of the lemming Lemmus lemmus in Europe; Frenkelia sp. (Sebek, 1975) from the brain of the field mouse Apodemus flavicollis in Europe; and Sarcocystis sp. (Ryan, Wyand & Nielsen, 1982) from the skeletal muscles of the muskrat Ondatra zibethica in North America.

The taxonomy of Sarcocystis (Protozoa, Apicomplexa) species.

The taxonomy of the heteroxenous apicomplexan protozoan genus Sarcocystis was reviewed, and a list of 122 species with their synonyms and hosts given. Both definitive and intermediate hosts are known for only 56 species. The fine structure of the sarcocyst wall may change with age and is not considered necessarily satisfactory for separating species. Specificity for the intermediate host is not narrow for all species. Earlier work on transmission of the parasite from one intermediate host to another should be repeated in the light of present knowledge of the life cycle of species of Sarcocystis.

Erhardorina n. g., Ascogregarina polynesiensis n. sp., Eimeria golemanskii n. sp., Isospora tamariscini n. sp., Gregarina kazumii n. nom., new combinations and emendations in the names of apicomplexan protozoa.

On the basis of a review of the approximately 4300 species of apicomplexan protozoa, the following new species, new names, new combinations, and emendations are given: NEW GENUS, Erhardovina; NEW SPECIES, Ascogregarina polynesiensis, Eimeria golemanskii, Isospora tamariscini; NEW NAME, Gregarina kazumii; NEW COMBINATIONS, Ascogregarina brachyceri (Purrini, 1980), Erhardovina euzeti (Lipa, 1981), E. scutovertexi (Erhardová, 1955), Haemorhormidium batrachi (Chaudhuri & Choudhury, 1983); EMENDATIONS, Selenidium francianum (Arvy, 1952) Tuzet & Ormières, 1965, Pyxinioides bolitoides D. P. Henry, 1938, P. japonicus H. Hoshide, 1951, P. kamenote H. Hoshide, 1951, P. kurofuji H. Hoshide, 1951, P. oshoroensis H. Hoshide, 1951, P. pugetensis D. P. Henry, 1938, Gregarina levinei Haldar & Sarkar, 1980, Retractocephalus halticae Haldar, Chakraborty & Kundu, 1982, Cnemidospora schizophylli Tuzet & Guerin, 1947, Grebneckiella indica (Merton, 1911) Watson, 1916, Quadruspinospora atractomorphae Haldar & Chakraborty, 1978, Haemogregarina acipenseri Nawrotzky, 1914, H. lobianci Yakimov & Kohl-Yakimov, 1912, H. yakimovikohlae Wladimiroff, 1910, Hepatozoon luehi (Sambon, 1909) Pessoa, Cavalheiro & de Souza, 1970, Eimeria beyerae Ovezmukhammedov, 1977, E. (?) gigantea (Labbé, 1896) Reichenow, 1921, E. (?) labbei Hardcastle, 1943, E. rufi Prasad, 1960, E. (?) scylii (Drago, 1902) Levine & Becker, 1933, Isospora corvi Ray, Shivnani, Oommen & Bhaskaran, 1952, I. melopsittaci Bhatia, Chauhan, Arora & Agrawal, 1973, I. seicerci Ray, Shivnani, Oommen & Bhaskaran, 1952, I. stomatici Chakravarty & Kar, 1944, I. triffitae Nukerbaeva & Svanbaev, 1973, Wenyonella mackinnonae Misra, 1947, Octosporella sanguinolentae Ovezmukhammedov, 1975, Lankesterella millani Alvarez Calvo, 1975, Sarcocystis woodhousei Dogel', 1916, Haemoproteus lari Yakunin, 1972, Babesia ninakohlyakimovae (Yakimoff & Shokhor, 1916), Theileria ninakohlyakimovae (Yakimov, 1916) Krylov, 1974, Haemohormidium batrachi (Chaudhuri & Choudhury, 1983).

Species of the coccidian genus Alveocystis.

Publications on the coccidia of certain invertebrates are reviewed and two new taxonomic-nomenclatural combinations are introduced: Alveocystis macrocoronata (Lüling, 1942) n. comb., in hosts Priapulus caudatus and Halicryptus spinulosus (Priapuloidea); and A. gugleri (Wacha, 1981) n. comb., in Triodopsis albolabris (Mollusca).

Eimeria beldingii n. sp. and other Coccidia (Apicomplexa) of the ground squirrel Spermophilus beldingi.

Fecal samples of 36 ground squirrels, Spermophilus beldingi, from Tioga Pass (elev. ca. 3315 m) in the Sierra Nevada, California, yielded oocysts of Eimeria beckeri in nine squirrels, E. citelli in four squirrels, E. beldingii n. sp. in two squirrels, and degenerated, unidentifiable oocysts in ten squirrels. Eimeria beldingii n. sp. oocysts are ellipsoidal, 30-34 X 24-30 (mean 32 X 26) micron with a two-layered, rough, striated wall, without a micropyle or residuum, with polar granules; they contain ellipsoidal or ovoid sporocysts 11-15 X 9-12 (mean 13 X 10) micron with a Stieda body and residuum.

Taxonomy and review of the coccidian genus Cryptosporidium (protozoa, apicomplexa).

Reports of Cryptosporidium in various hosts and cross-transmission experiments are reviewed. Cryptosporidium has been found in mammals (Primates, Artiodactyla, Perissodactyla , Carnivora, Lagomorpha, and Rodentia), birds, reptiles, and fish. The only cross-transmission attempts that have been made have been from mammals to other mammals and to a few birds. Names have been given to 19 "species," but it is concluded that only four of these should be considered valid at present. These are: C. muris Tyzzer, 1907 in mammals, C. meleagridis Slavin , 1955 in birds, C. crotali Triffit , 1925 in reptiles, and C. nasorum Hoover , Hoerr , Carlton , Hinsman & Ferguson, 1981 in fish.

Some corrections in Haemogregarine (Apicomplexa: Protozoa) nomenclature.

The nomenclature of three genera in the family Haemogregarinidae (Haemogregarina, Karyolysus, and Hepatozoon) has been reviewed and the following new names are introduced to replace homonyms or for previously unnamed species: haemogregarina carlosi n. nom., in the erythrocytes of the lizard Lacerta ocellata; Haemogregarina tincae n. nom., in the stomach and intestine of the tench Tinca tinca; Hepatozoon insectivorae n. sp., in the leucocytes of the shrews Sorex araneus and Crocidura leucodon; Hepatozoon krampitzi n. sp., in the leucocytes of the vole Microtus oeconomus; Hepatozoon peromysci n. sp., in the leucocytes of the deermice Peromyscus boylii and P. truei gilberti; and Hepatozoon pallida (Pessoa et al., 1971) n. comb., in the erythrocytes of the snake Thamnodynastes pallidus nattereri.

The genus atoxoplasma (Protozoa, Apicomplexa).

The apicomplexan protozoan genus Atoxoplasma Garnham, 1950 is resurrected and the family Atoxoplasmatidae n. fam. established for homoxenous blood parasites of birds that develop asexually in both the blood and intestinal cells, and form oocysts that are passed unsporulated in the feces, sporulate on the ground, and then infect new hosts. A list of 19 species of Atoxoplasma is given. Atoxoplasma desseri n. sp. of the evening grosbeak Coccothraustes vespertinus and rose-breasted grosbeak Pheucticus ludovicianus is named.

Eimeria and sarcocystis in raccoons in Illinois.

Eimeria nuttalli oocysts were found in 58% (21/36) and E. procyonis oocysts in 25% (9/36) of raccoons Procyon lotor in Illinois, and sporocysts of Sarcocystis sp. in 17% (2/12) of other raccoons in Illinois. The oocysts of E. nuttalli were ellipsoidal to ovoid, 15-21 X 12-17 micrometer, with a one-layered, smooth, colorless wall. The oocysts of E. procyonis were 22-28 X 18-22 micrometer, with a rough, striated, brownish, two-layered wall. The sporulated sporocysts of Sarcocystis sp. were 11-13 X 8-10 micrometer. Attempts to infect baby pigs by feeding them sporocysts of Sarcocystis sp. from the reaction failed.

Some corrections of coccidian (Apicomplexa: Protozoa) nomenclature.

The following nomenclatural corrections and changes are introduced for the coccidia. NEW SPECIES: Cryptosporidium rhesi from the rhesus monkey Macaca mulatta; Cryptosporidium serpentis from the snakes Elaphe guttata, Elapha subocularis, Crotalus horridus, and Sanzinia madagascarensis; Eimeria perazae from the lizard Cnemidophorus l. lemniscatus; and Eimeria tarichae from the salamander Taricha toirosa. NEW COMBINATIONS: Orcheobius carinii for Cariniella carinii from the frog Leptodactylus ocellatus; Schellackia iguanae for Lainsonia iguanae from the iguana Iguana iguana; Schellackia weinbergi for Haemogregarina weinbergi from the lizard Tupinambis nigropunctatus; Dorisa harpia for Dorisiella harpia from the bat Harpiocephalus harpia lasyurus; Barrouxia labbei for Echinospora labbei from the centipedes Lithobius mutabilis and L. pyrenaicus; and Barrouxia ventricosa for Echinospora ventricosa from the centipede Lithobius hexodus. The generic names Lainsonia and Gordonella are synonymized with Schellackia; Echinospora with Barrouxia; and Cariniella with Orcheobius.

Five new species of Isospora from Hawaiian birds.

The following species are described from Hawaiian birds: Isospora brayi sp. n., with oocysts 27 X 26 micron and sporocysts 19 X 12 micron, from the Japanese white-eye, Zosterops japonicus Temminck & Schlegel; Isospora cardinalis sp. n., with oocysts 24 X 23 micron, and sporocysts 16 X 10 micron, from the cardinal, Cardinalis cardinalis (Linnaeus); Isospora ivensae sp. n., with oocysts 26 X 25 micron, and sporocysts 18 X 12 micron, from the spotted or white-throated munia, Lonchura punctulata (Linnaeus); Isospora loxopis sp. n., with oocysts 26 X 23 micron, and sporocysts 16 X 13 micron, from the amakihi or honeycreeper, Loxops virens (Gmelin); and Isospora phaeornis sp. n., with oocysts 27 X 19 micron, and sporocysts 16 X 11 micron, from the omao or Hawaiian thrush, Phaeornis obscurus (Gmelin). All the host birds belong to the order Passerorida.

A newly revised classification of the protozoa.

The subkingdom Protozoa now inclues over 65,000 named species, of which over half are fossil and approximately 10,000 are parasitic. Among living species, this includes approximately 250 parasitic and 11,300 free-living sarcodines (of which approximately 4,600 are foraminiferids); approximately 1,8000 parasitic and 5,100 free-living flagellates; approximately 5,600 parasitic "Sporozoa" (including Apicomplexa, Microspora, Myxospora, and Ascetospora); and approximately 2,5000 parasitic and 4,700 free-living ciliates. There are undoubtedly thousands more still unnamed. Seven phyla of PROTOZOA are accepted in this classification--SARCOMASTIGOPHORA, LABYRINTHOMORPHA, APICOMPLEXA, MICROSPORA, ASCETOSPORA, MYXOSPORA, and CILIOPHORA. Diagnoses are given for these and for all higher taxa through suborders, and reporesentative genera of each are named. The present scheme is a considerable revision of the Society's 1964 classification, which was prepared at a time when perhaps 48,000 species had been named. It has been necessitated by the acquisition of a great deal of nex taxonomic information, much of it through electron microscopy. It is hoped that the present classification incorporatesmost of the major changes that will be made for some time, and that it will be used for many years by both protozoologist and non-protozoologists.