Human catalase: looking for complete identity

Abstract

Catalases are well studied enzymes that play critical roles in protecting cells against the toxic effects of hydrogen peroxide. The ubiquity of the enzyme and the availability of substrates made heme catalases the focus of many biochemical and molecular biology studies over 100 years. In human, this has been implicated in various physiological and pathological conditions. Advancement in proteomics revealed many of novel and previously unknown features of this mysterious enzyme, but some functional aspects are yet to be explained. Along with discussion on future research area, this mini-review compile the information available on the structure, function and mechanism of action of human catalase.

Evaluation of basil extract ( Ocimum basilicum L.) on oxidative, anti-genotoxic and anti-inflammatory effects in human leukocytes cell cultures exposed to challenging agents

“…Mammalian cells have elaborate antioxidant defense mechanisms to control damage effects of reactive oxygen species and the catalase enzyme is one of these, protecting cells against the toxic effects of hydrogen peroxide (Goyal, Basak, 2010). The results of catalase analysis show the ability of O. basilicum extract in neutralizing the effects of hydrogen peroxide.…”

Hydroxyl Radical Generation Theory: A Possible Explanation of Unexplained Actions of Mammalian Catalase

“…HRGT explains the generation of inactive compound-II along with production of HRs. It also explains relatively slow conversion of compound-II into the resting state enzyme [4].…”

“…It catalyses the dissociation of hydrogen peroxide directly into H 2 O and O 2 . The altered catalase activity has been observed in number of disease conditions [2][3][4]. The crystal structure of tetrameric human erythrocyte catalse (HEC) has been identified which was very similar to those of bovine liver catalase (BLC) [5,6] with functionally important amino acid sequences conserved [7].…”

“…Though the above mechanism is widely accepted and overall explains the catalytic reaction but leave many aspects mystified; summarized in Table 1 and 2 [3,4]. The catalytic reaction and HRG mechanism.…”

Genetics of Endothelial Damage Associated to Diabetes Mellitus Type 2

“…SOD enzymes are classified into three groups: cytosolic CuZn-SOD, mitochondrial Mn-SOD, and extracellular Ec-SOD (Zelko et al, 2002). Catalase is present as a dumbbell-shaped tetramer of four identical subunits in peroxisomes and removes hydrogen peroxide molecules that are byproducts of the SOD reaction (Goyal & Basak, 2010).…”