AgriMyc

Phylum	Class	Order	Family	Genus	Species/Subspecies

Species/Subspecies:

Cryptococcus neoformans subsp. neoformans

Categories:

Animal pathogen; human pathogen

Etymology:

Genus name: hidden berry.
Species epithet: new form.
Subspecies epithet: see Species epithet.

Alternative Species Name(s):

Filobasidiella neoformans, som är namnet på den teleomorfa formen.

Significance:

A common pathogenic fungus in immunocompromised individuals.
[Important]

Taxonomy:

Phylum	Class	Order	Family	Genus
Basidiomycota	Tremellomycetes	Tremellales	Tremellaceae	Cryptococcus

Macromorphology (smell):

On SDA , the fungus forms cream-coloured, mucoid yeast-like colonies. On bird seed agar, the fungus produces melanin and the colonies then turn dark brown.

Micromorphology:

C. neoformans subsp. neoformans has round or oval yeast-like cells, which are 4-6 µm in diameter. The cells are surrounded by a capsule that can be up to 30 µm thick.

Metabolism:

Obligate aerobe

Reproduction:

Har asexuell och sexuell reproduktion. Den asexuella reproduktionen sker genom avknoppning och den sexuella genom konjugation av två jässtceller som bilder hyfer. På hyferna bildas basidier, som producerar en lång kedja av basidiosporer.

Spec. Char.:

This fungus is radiation resistantradio resistant.

Reservoir:

Pigeon droppings, droppings from other birds and soil enriched by bird droppings.

Disease/effect:

Cryptococcosis

Hosts/substrate:

Cat, dog, cattle, horse and humans.

Clinical Picture:

Cryptococcosis mainly affects cats (infections of the respiratory system, nervous system and the eye), but can also affect dogs (disseminated infection with symptoms from nervous system and eyes), cattle (mastitis and nasal granulomas), horses (nasal granulomas, sinusitis, skin lesions, pneumonia, meningoencephalitis and abortion), sheep, birds and wild animals. In the case of humans, it is mainly immunocompromised patients, who are affected. However also immunocompetent persons may contract cryptococcosis.

Virulence Factors:

Polysaccharide capsule, which consists of 1,3-mannopyranose residues and allows the fungus to avoid the host's immune system. Melanin, which prevents the fungus from dying from oxidative stress after phagocytosis of macrophages.

Genome Sequence:

ACC-No GenBank	Strain/Isolate	# of chrom	Size (Mbp)
GCF_000091045	JEC21	14	19.1

18S rRNA Seq:

ACC-No GenBank	Strain/Isolate	Number of NT
BR000310	B3501A	3391

ITS regions:

ACC-No GenBank	Strain/Isolate	Number of NT	Genes
NR_171785	ATCC 32045^TM	554	ITS 1, 5.8S rRNA, ITS 2, 28S rRNA

Taxonomy/phylogeny:

About 40 species have been described within the genus Cryptococcus, but the taxonomy is under revision. Four species are considered infectious, namely: C. neoformans, C. gattii, C. albidus and C. uniguttulatus. C. gattii will possibly be divided into four additional species. It has been suggested that the name of Cryptococcus neoformans subsp. neoformans should be exchanged with Cryptococcus deneoformans.

Reference(s):

No. 27, 28

Updated:

2022-06-22