Redundancy, phylogeny and differential expression of Histoplasma capsulatum catalases The GenBank accession numbers for the cDNA sequences reported in this paper are AF139985 (CATB), AF189368 (CATA) and AF189369 (CATP).

Abstract

Histoplasma capsulatum produces an extracellular catalase termed M antigen, which is similar to catalase B of Aspergillus and Emericella species. Evidence is presented here for two additional catalase isozymes in H. capsulatum. Catalase A is highly similar to a large-subunit catalase in Aspergillus and Emericella species, while catalase P is a small-subunit catalase protein with greatest similarity to known peroxisomal catalases of animals and Saccharomycotina yeasts. Complete cDNAs for the CATA and CATP genes (encoding catalases A and P, respectively) were isolated. The transcriptional expression of the H. capsulatum CATA, CATB (M antigen) and CATP genes was assessed by Northern blot hybridizations on total RNA. Results at the transcript levels for these genes are shown for three conditions : cell morphology (mycelial versus yeast phase cells), oxidative stress (in response to a challenge with H 2 O 2 ) and carbon source (glucose vs glycerol). Collectively, these results demonstrated regulation of CATA by both cell morphology and oxidative stress, but not by carbon source, and regulation of CATB and CATP by carbon source but not cell morphology or oxidative stress. A phylogenetic analysis of presently available catalase sequences and intron residences was done. The results support a model for evolution of eukaryotic monofunctional catalase genes from prokaryotic genes.

TheCryptococcus neoformansCatalase Gene Family and ItsRole in Antioxidant Defense

“…We performed a phylogenetic analysis of multiple fungal catalases, revealing four clades, consistent with previous findings (24,27): clades P (peroxisomal catalases), C (cytoplasmic catalases), A (spore-specific catalases), and B (secreted catalases) (Fig. 1).…”

Purification and Characterization of a Mycelial Catalase from Scedosporium boydii, a Useful Tool for Specific Antibody Detection in Patients with Cystic Fibrosis

“…Consequently, S. boydii catalase A1 can be classified in clade 2 of the catalase phylogenetic tree (36,37), which corresponds to the so-called atypical monofunctional catalases characterized by large subunits, a broad pH range, susceptibility to 3-AT, and resistance to SDS and ethanol-chloroform (38), like Escherichia coli HP-II catalase (39), A. niger CatR (40), and Neurospora crassa Cat1 (41). Moreover, detection of catalase A1 in the culture supernatant demonstrates its secretion in the environment, therefore indicating that it belongs to clade B of fungal catalases, which comprise secreted monofunctional catalases (42,43).…”

A Eukaryote without Catalase-Containing Microbodies: Neurosporacrassa Exhibits a Unique Cellular Distributionof Its Four Catalases

“…A phylogenetic analysis of catalases conducted by Johnson et al (22) revealed that CAT-4 belongs to the family of small monofunctional catalases that are found in bacteria, animals, and fungi. Since this clade includes all known peroxisomal catalases, it was tempting to assume that CAT-4 is also a peroxisomal protein.…”

“…We and others (22) have searched the N. crassa genome sequence for the presence of catalase isozymes. Interestingly, there is indeed a fourth open reading frame with strong similarity to that for the catalases, NCU05169.2, hereafter referred to as cat-4 (Fig.…”

“…Evidence exists that CAT-3 is processed and secreted; however, since only a little extracellular CAT-3 activity has been found, it has been suggested that most of the enzyme is either bound to the cell wall or remains within the cell (34). Completion of the N. crassa genome (14) revealed a fourth putative catalase that belongs to the family of small-subunit monofunctional catalases and is most similar to peroxisomal catalases of animals and yeasts (22). Thus, current knowledge is commensurate with the existence of a peroxisomal compartment in N. crassa that is distinct from glyoxysomes.…”