F0007 - Phylum Zygomycota and the new classification - Univap

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Zygomycetes• Esporangio contendo 1-50 esporos• Merosporangio éesporangioles comesporos em sérieslinearesesporangiolesZygomycota DENR 19Zygomycota DENR 20sporangiosporessporangiophorecolumellaZygomycota DENR 21 Zygomycota DENR 22Microscopic features of Rhizopus spp. inculture. (A) Low-power magnification (×4) ofRhizopus demonstrates the nodal occurrence ofwell-developed rhizoids in this genus(arrowhead). Sporangiophores are long andunbranched, usually terminating in largeglobose sporangia. In this figure, the sporangiahave become deliquescent, releasing a plethoraof sporangiospores seen dispersed in thebackground. The naked, somewhat collapsedcolumellae remain at the distal end of thesporangiophores (arrows). The sporangiophorethemselves are pigmented light brown. Bar,200 µm. (B) Rhizoids originate directly at thebase of the sporangiophores, often from agnarled, pigmented knot at the node(arrowhead). Stolons extend laterally from thenode (long arrows). The naked columella haspartially collapsed back on the sporangiophore(asterisk). At this higher power ofmagnification, the round to ovalsporangiospore morphology is readilyappreciated (short arrows). Bar, 25 µm. (C) Anintact, mature globose sporangium is seen inthis photomicrograph (arrow). The sphericalcolumella is nearly obscured by the presence ofthe sporangiospores in the sporangial sack. Aflattened, bare columella is also present,illustrating well the slight apophysis that isoften seen in the Rhizopus spp. (arrowhead).Bar, 50 µm. (D) Upon deliquescence, smallsporangial membrane remnants may adhere atthe interface between the apophysis and thecolumella. These remnants are referred to asthe collarette and are well illustrated in thisphotomicrograph (arrowheads). Note also theClinical Microbiology Reviews, April 2000, p. 236-301, Vol. 13, No. 2very slight apophysis at the top of theZygomycetes in Human Disease Zygomycota DENR sporangiophore. This columella is intact 23 anddemonstrates the oval shape that may be seenJulie A. Ribes, Carolyn L. Vanover-Sams, and Doris J. Bakerin Rhizopus isolates. Bar, 25 µm.Clinical Microbiology Reviews, April 2000, p. 236-301, Vol. 13, No. 2Zygomycetes in Human DiseaseJulie A. Ribes, Carolyn L. Vanover-Sams, and Doris J. BakerReproductive structures of the Mucorales. (A) Sporangium. Development of asexual sporangiospore in sacks called sporangia is characteristic of the families Mucoraceae and Saksenaea.The aerial mycelium of these organisms terminate in swollen structures that develop into sporangial sacks and columellae. Sporangiospores develop asexually by free-cell cleavagewithin the sporangial membrane. At maturity, the sporangium of the Mucorales becomes deliquescent, releasing the sporangiospores. A related mechanism where sporangiospores arereleased from the sporangiospore by dissolution of a gelatinous plug is seen for Saksenaea vasiformis. The fungus pictured here demonstrates the sporangium produced by Mucor spp.Bar, 20 µm. (B) Merosporangia. Cylindrical or finger-like projections surround a swollen vesicle in this isolate of Syncephalastrum racemosum. A single row of sporangiospores forminside these tubular merosporangia (arrowhead). Spores may be released as entire merosporangial units or singly as the merosporangial membrane dissolves. This form ofreproduction is characteristic of S. racemosum. Bar, 20 µm. (C and D) Sporangiola. Sporangiola or conidia develop singly around a swollen vesicle on stalks called sterigmata. Singlecelled sporangiola (arrowhead), typically produced by members of the genus Cunninghamella (C), are often echinate and form on short sterigmata. Those produced by Cokeromycesrecurvatus (D) are multicelled (arrowhead) and occur on long recurving stalks. Bar, 20 µm. (E) Yeast. Several members of the order Mucorales are dimorphic. Yeast forms have beenidentified in vivo for some Mucor spp. as well as Cokeromyces recurvatus (pictured here). Yeast production in vitro often requires increased temperature of incubation, high carbondioxide tension, or anaerobic culture conditions. Bar, 20 µm. (F and G) Chlamydospores and gemmae. These asexual reproductive structures are derived from the vegetative hyphaeof certain species of the Mucorales. Chlamydospores may be formed intercalated with the mycelium (endogenous formation) (arrowhead in panel F), while gemmae are separated fromthe mycelium and often demonstrate yeast-like budding (exogenous formation) (G). Chlamydospores and gemmae are often considered together, since they may be difficult todifferentiate and are similarly derived. These are produced by some but not all members of the Mucorales. Their morphology may vary substantially but is not particularly useful forspecies determination (355). Bar, 40 µm. (H) Zygospores. This is the only form of sexual reproduction employed by the zygomycetes. Zygospores may form within a single isolatewithout mating (homothallic reproduction) or may require mating with an appropriately oriented mating strain (heterothallic reproduction). Zygospore morphology is oftencharacteristic for an organism when color, size, shape and surface decoration Zygomycota are taken into account. DENR Mating of two isolates to produce mature zygospores provides definitive 24taxonomic identification of an unknown isolate. The zygospores pictured here are from Cokeromyces recurvatus. Bar, 40 µm.4
Clinical Microbiology Reviews, April 2000, p. 236-301, Vol. 13, No. 2Zygomycetes in Human DiseaseJulie A. Ribes, Carolyn L. Vanover-Sams, and Doris J. BakerSchematic diagram labeling the morphologic structures seen inthe sporangium-producing Mucorales (A) Rhizopus spp. (B)Apophysomyces elegans.Zygomycota DENR 25Gross morphology of Rhizopus, Mucor, and Absidiaisolates in culture. (A) Rhizopus gross morphology onSABHI medium. Rhizopus spp. typically produce avery high, fibrous colony that rapidly fills the entirepetri dish. This isolate has expanded to the lid(known as a "lid lifter"). It has produced abundantpigmented sporangia, which are seen as the dark areaspeppering the otherwise pale mycelium. Thismorphology is characteristic of the Rhizopus spp. (B)Low-growing Mucor variant gross morphology onSABHI medium. Mucor spp. will show variation fromculture to culture. This particular isolate has produceda low-growing, fibrous colony morphology thatreadily demonstrates the "woolly" or floccose growthcharacteristic of the Mucoraceae. Pigmentation is alsovariable, both within and among the Mucor spp.Increased pigmentation is generally reflective of areasof the mycelium that are rich in sporangia. Dependingon the individual isolate, Mucor may be extremelyfloccose or low growing and may range from purewhite to shades of gray or brown. (C) Absidiacorymbifera gross colony morphology on SABHImedium. A. corymbifera produces a light-coloredmycelium, generally cream or gray. The pepperedappearance seen in the Rhizopus spp. is lacking despitethe production of abundant sporangia. The myceliumof this isolate is firmly plastered to the lid of the petridish, consistent with the lid-lifting properly of thisfungus. (D) A. corymbifera, reverse side of the cultureplate shown in panel C. The Mucoraceae are hyalinemolds that produce a pale reverse in culture onstandard media such as SABHI agar. Although someisolates such as Rhizopus spp. may have lightlypigmented hyphal elements, this is generally reflectedas a pale yellow or brown reverse and not the darklyClinical Microbiology Reviews, April 2000, p. 236-301, Vol. 13, No. 2 pigmented reverse of the dematiaceous fungi.Zygomycetes in Human DiseaseZygomycota DENR 26Julie A. Ribes, Carolyn L. Vanover-Sams, and Doris J. BakerGross morphology of Basidiobolus, Conidiobolus,and Mucor colonies in culture. (A) Basidiobolusmicrosporus colony morphology on SABHI agar.Dense, waxy, folded, or furrowed colonies areproduced on standard culture media. Coloniesare low growing, lacking the floccosemorphology seen in the typical isolate of theMucorales (see Mucor morphology in panel B).This isolate produced a brownish orange colonythat was pale on reverse. (B) Mucor colonymorphology on SABHI agar. The floccose or"woolly" colony morphology produced by mostof the Mucorales is well demonstrated in thisMucor isolate. Contrast the fibrous aerialmycelium with the glabrous morphology seenfor both Basidiobolus (A) and Conidiobolus (C).Basidiobolus microsporusThis difference in colony morphology is one ofthe distinguishing features between the Mucoralesand the Entomophthorales. (C) Conidioboluscoronatus colony morphology on Sabourauddextrose agar slant. Similar to Basidiobolus spp.,Conidiobolus spp. produce low-growing waxy (orsometimes powdery) folded and furrowedcolonies that lack aerial mycelium. Satellitecolonies arising from germination of ejectedsporangiospores has lead to confluent growth inthis tube containing a 6-week-old culture. (D)Conidiobolus coronatus tube culture, side view ofthe tube in panel C. Note the cloudy appearanceof the glass surface of the tube. This isproduced by the collection of a plethora offorcibly expelled sporangiospores which haveClinical Microbiology Reviews, April 2000, p. 236-301, Vol. 13, No. 2become encrusted on the inside surface of thetube. This opacification of the culture tube (orZygomycetes in Human Disease Zygomycota DENRpetri dish lid) is characteristic of this organism.27Julie A. Ribes, Carolyn L. Vanover-Sams, and Doris J. BakerZygomycetes• O processo da reproduçãosexual consiste da fusão de doisgametângios dando a origem aum zigosporo (esporo de repousocom parede espessa) dentro de umzigosporângioZygomycota DENR 28Compatibilidade Sexual• Regulamentado pela ácido trispórico, umferomônio sexual (Blakeslee, 1904):– Aumenta a secreção de determinados precursoresde ácido trispórico e beta-caroteno– Positivamente regulamenta a sua própria síntese,estimulando a taxa precursores da formação emculturas pareadas– Induz a formação zigosporangio– Reprime formação do esporangióforoZygomycota DENR 29Zygomycetes• Homotálico – requer apenas um talo(hifa) para reprodução sexual• Heterotálico – requer dois talos (hifas) desexos opostos para reprodução sexual,designadas mais (+) ou menos (-)– Sexual spore produced by conjugation when(+) hyphae e (-) fuse is calledzygosporangiumZygomycota DENR 305
Page 1 and 2: PhylumZygomycotaZygomycota DENR 1Zy
Page 3: Zygomycota• Classe Zygomycetes- A
Page 7 and 8: ZygomycetesZygomycota DENR 37 Zygom
Page 9 and 10: Ordem Mucorales• Aplicações ind
Page 11 and 12: Phycomyces• The sensitivity of Ph
Page 13 and 14: Mucormicose• Diabetes não contro
Page 15 and 16: Entomophthora muscaeOrdem Entomopht
Page 17 and 18: Ordem Zoopagales• Five families,
Page 19 and 20: PhylumGlomeromycotaOrdem GlomalesZy
Page 21 and 22: Phylum Glomeromycota• Order Gloma
Page 23: Phylum GlomeromycotaSpore of Entrop

F0007 - Phylum Zygomycota and the new classification - Univap

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