Oomycetes -Cell Walls - Non-elaborates posts - Post 1

 

 

In the case of oomycetes, the nature of this boundary reveals both their evolutionary distinctness and their hidden kinship with other eukaryotic lineages. Unlike the true fungi, whose cell walls are dominated by chitin, the oomycetes construct their cellular armor primarily from cellulose and β-glucans. This simple chemical divergence carries profound biological, evolutionary, and ecological implications.

Cellulose, the same polymer that fortifies the cell walls of plants, endows oomycetes with a molecular identity that blurs the traditional lines between microbial kingdoms. Its linear chains of β-1,4-linked glucose create crystalline microfibrils, conferring both rigidity and tensile strength. Interwoven with β-1,3- and β-1,6-glucans, the wall achieves a balance between firmness and flexibility, allowing the organism to withstand osmotic pressures while remaining metabolically active. This unique biochemical composition not only distinguishes oomycetes from fungi but also aligns them, at least superficially, with photosynthetic lineages in the Stramenopila, thereby affirming their phylogenetic placement.

 

(To be revised, perhaps (soon))

Comments

Post a Comment

Popular posts from this blog

   At the biochemical level, ERG11 ’s function as a heme-dependent monooxygenase interlocks with the cell’s oxidative balance. Heme fluctuations within the nucleus can alter the activity of heme-responsive transcription factors and chromatin modifiers, introducing a chemical feedback loop between metabolism and genetic variation (Puig & Gutiérrez, 2022). Reactive oxygen species generated by azole stress promote DNA oxidation and base substitution events preferentially within open chromatin domains. This coupling of redox chemistry with mutation formation constitutes a nuclear-scale biochemical evolution engine—one where chemical disequilibrium catalyzes genomic diversity in real time.
Read more

Fungi - Candida auris - Non-Elaborate Posts - Post 2

Genetics and genetic mutations for resistance to fluconazole ERG11 mutations (notably Y132F, K143R) are common contributors to fluconazole resistance; and Cas9 editing showed direct contribution of these alleles to elevated MICs. Additional determinants (TAC1B, efflux pumps, aneuploidy) amplify resistance. Different geographic clades show distinct ERG11 allele frequencies. Genome assemblies reveal structural variation and copy-number differences Resistance evolves under strong antifungal selection in hospitals. Surveillance sequences help track clonal spread and mutation patterns
Read more
In some settings, susceptible-dose dependent (SDD) categorization is used: isolates with intermediate MICs may still respond to higher fluconazole doses, but the presence of ERG11 mutations often reduces the likelihood of clinical success even with dose escalation. ( PMC ) Beyond single substitutions, clinical isolates frequently carry combinations of ERG11 changes plus efflux-regulatory mutations (e.g., TAC1 gain-of-function) that together produce higher MICs and poorer outcomes; thus, sequencing plus expression data can refine prognostic interpretation.
Read more