Tony--fyi

[Guest guest]

This classification conveys important information about the

biochemistry and metabolism of disease-causing organisms. Here are

three examples. 1) Pneumocystis, an opportunistic pathogen causing

mortality in AIDS patients and immunocompromised individuals, is now

known to be a fungus, indicating a different treatment regimen is

needed. 2) Phytophtora, an organism causing potato blight, such as

the one that caused the Irish famine in the 19th century, is now

known not to be a fungus, which explains why fungicides are not

effective treatments. 3) Plasmodium, the causative agent of malaria,

is now known to share ancestry with photosynthetic organisms and has

a vestigial chloroplast, called the apicoplast. This knowledge opens

exciting possibilities for novel drug therapies.

The new classification recognizes 6 major clusters of organisms,

rather than the 4 traditional Kingdoms. These clusters are 1) the

Opisthokonta, grouping the animals, fungi, choanoflagellates, and

Mesomycetozoa; 2) the Amoebozoa, grouping most traditional amoebae,

slime moulds, many testate amoebae, some amoebo-flagellates, and

several species without mitochondria; 3) the Excavata, grouping

oxymonads, parabasalids, diplomonads, jakobids, and several other

genera of heterotrophic flagellates, and possibly including the

Euglenozoa and Heterolobosea; 4) the Rhizaria, grouping the

Foraminifera, most of the traditional Radiolaria, and the Cercozoa

with filose pseudopodia, such as many amoebo-flagellates and some

testate amoebae; 5) the Archaeplastida, grouping the Glaucophyta, red

algae, green algae, and Plantae; 6) the Chromalveolata, grouping the

Alveolata (including ciliates, the dinoflagellates, and the

Apicomplexa), cryptophytes, haptophytes, and stramenopiles (including

brown algae, the diatoms, many zoosporic fungi, opalinids, amongst

others).

Finally, the authors noted that they " adopted a hierarchical system

without formal rank designations, such as " class, " " sub-

class, " " super-order " or " order, " The decision to do so has been

primarily motivated by utility, to avoid the common problem of a

single change causing a cascade of changes to the system. We believe

this to be more utilitarian, and less problematic than traditional

conventions, as it is not constrained by formally attributing a

limited number of rank names. "

---

It's sort of amusign they say, " so it's not a fungus that's why

fungidicides didn't work! " LOL. BUt not so LOL when its a human

infection. BTW, I find the apicoplast really fascinating as I said. I

really want to do a story on it but I " m not sure where to place it. I

really should query around. I feel overwhelmed right now tho.