Hydrophilins in the filamentous fungus Neosartorya fischeri (Aspergillus fischeri) have protective activity against several types of microbial water stress

Abstract

Hydrophilins are proteins that occur in all domains of life and protect cells and organisms against drought and other stresses. They include most of the late embryogenesis abundant (LEA) proteins and the heat shock protein (HSP) Hsp12. Here, the role of a predicted LEA-like protein (LeamA) and two Hsp12 proteins (Hsp12A and Hsp12B) of Neosartorya fischeri was studied. This filamentous fungus forms ascospores that belong to the most stress-resistant eukaryotic cells described to date. Heterologous expression of LeamA, Hsp12A and Hsp12B resulted in increased tolerance against salt and osmotic stress in Escherichia coli. These proteins were also shown to protect lactate dehydrogenase against dry heat and freeze-thaw cycles in vitro. Deletion of leamA caused diminished viability of sexual ascospores after drought and heat. This is the first report on functionality of Hsp12 and putative LeamA proteins derived from filamentous fungi, and their possible role in N. fischeri ascospore resistance against desiccation, high temperature and osmotic stress is discussed.

Functional assessment of hydrophilic domains of late embryogenesis abundant proteins from distant organisms

“…Late embryogenesis abundant proteins were first characterized in cotton seeds three decades ago and are hydrophilic (Dure and Galau, ); their accumulation simultaneously occurs alongside seed maturation, desiccation and other forms of (a) biotic stresses (Chakrabortee et al ., ; Hatanaka et al ., ; Liu et al ., ; Leeuwen et al ., ; Bremer et al ., ). Continuous engagement in research on LEA proteins has shown us that these family proteins are not restricted to plants, as they have also been documented in bacteria, fungi and animals (Hand et al ., ).…”

Insights on Structure and Function of a Late Embryogenesis Abundant Protein from Amaranthus cruentus: An Intrinsically Disordered Protein Involved in Protection against Desiccation, Oxidant Conditions, and Osmotic Stress

“…LEA proteins were originally discovered in cotton ( Gossypium hirsutum ) seeds (Dure, 1989), but their accumulation is not only related to the development of desiccation tolerance in orthodox seeds (desiccation-tolerant seeds). LEA proteins are also induced upon water-related stress in plant vegetative tissues and in other anhydrobiotic organisms such as eubacteria, rotifers, nematodes, tardigrades, arthropods (Ingram and Bartels, 1996; Browne et al, 2002; Hundertmark and Hincha, 2008; Campos et al, 2013; Hatanaka et al, 2014; van Leeuwen et al, 2016). In some microorganisms, LEA proteins are reported in response to water limitation, which suggests that they have an important role in desiccation tolerance (Tunnacliffe and Wise, 2007; Tunnacliffe et al, 2010; Hand et al, 2011).…”

Pleiotropic roles of late embryogenesis abundant proteins of Deinococcus radiodurans against oxidation and desiccation

“…LEA proteins were intensely studied in plants and classified into seven distinct groups according to the variance of their motifs that are strongly induced under water-loss conditions, oxidation and desiccation [30] , [31] , [32] . Previous studies of LEA proteins are restricted to eukaryotes, especially plants, but less was known about their function and underlying mechanisms in bacteria and archaea, even both were genetically annotated with diverse LEAs [21] , [22] , [33] .…”