Alternaria alternata (A. alternata)

Alternaria alternata is a ubiquitous ascomycete fungus and a common environmental mold that acts as both a significant plant pathogen and a potent human allergen. It is not a single molecular target but a whole organism; however, it is frequently cited in clinical contexts as the target for antifungal therapies and allergen-specific immunotherapy. The fungus is a major risk factor for the development and exacerbation of severe asthma and allergic rhinitis, with its major allergen, Alt a 1, playing a central role in airway inflammation and sensitization (Gabriel et al., 2016). In immunocompromised individuals, it can cause opportunistic infections known as alternariosis, affecting the skin, sinuses, or lungs (Pastor & Guarro, 2008). Therapeutic intervention typically involves the use of triazole or polyene antifungals to disrupt fungal cell membrane integrity, or the administration of standardized Alternaria extracts to modulate the patient's immune response in allergic disease (Bush & Prochnau, 2004).

Other names

Alternaria tenuisTorula alternataEarly blight fungusBlack mold

Antifungal agents target the organism by binding to ergosterol to form membrane pores (polyenes) or inhibiting lanosterol 14-alpha-demethylase to prevent ergosterol synthesis (azoles); allergenic extracts are used in immunotherapy to induce immune tolerance through desensitization.