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Background Invasive aspergillosis (IA) is most commonly caused by the morphospecies Aspergillus fumigatus. However, genetic-based methods indicate that organisms phenotypically identified as A. fumigatus actually constitute a mold complex, designated Aspergillus section fumigati subgenus fumigati. Methods Multilocus sequencing and analysis was performed on fungi identified as A. fumigatus from the clinical culture collection maintained at the National Institutes of Health from 2000 through 2008, with a focus on the internal transcribed spacer 1 and 2 regions of ribosomal DNA (rDNA), b-tubulin, and rodlet A genes. We reviewed the medical records, radiology, and histopathology of corresponding patients. To confirm identification of Neosartorya udagawae isolates, mating studies were performed with reference strains. Antifungal susceptibility testing was performed by broth microdilution and read at 48 hours. Results Thirty-six cases of infection attributed to A. fumigatus were identified; 4 were caused by N. udagawae (3 in patients with chronic granulomatous disease and 1 in a patient with myelodysplastic syndrome). Disease due to N. udagawae was chronic, with a median duration of 35 weeks, compared with a median duration of 5.5 weeks for patients with chronic granulomatous disease who had infection due to A. fumigatus sensu stricto (P < .05, Mann-Whitney U test). Infection spread across anatomical planes in a contiguous manner and was refractory to standard therapy. Two of the 4 patients died. N. udagawae demonstrated relatively higher minimum inhibitory concentrations to various agents, compared with those demonstrated by contemporary A. fumigatus sensu stricto isolates. Conclusions To our knowledge, this is the first report documenting infection due to N. udagawae. Clinical manifestations were distinct from those of typical IA. Fumigati-mimetics with inherent potential for antifungal resistance are agents of IA. Genetic identification of molds should be considered for unusual or refractory IA.

DNA damage triggers the assembly of checkpoint signaling proteins on chromatin that activate the Chk1 signaling pathway and block S-phase progression. Here we show that genotoxin-induced Chk1 activation requires Cut5 (Mus101/TopBP1) in a process that is independent of the role of Cut5 in DNA replication. Analysis of the role of Cut5 in checkpoint activation revealed that it associated with chromatin following DNA damage in a process that required RPA. Additionally, Cut5 was required for the recruitment of Atr, DNA polymerase ␣, and Rad1 but not RPA to chromatin following DNA damage. Taken together, these results demonstrate that Cut5 plays an integral role in the recruitment and assembly of the Chk1 signaling cascade components following DNA damage.Checkpoint signaling pathways maintain genomic integrity by blocking cell cycle progression, influencing DNA repair, and in the event of severe DNA damage, prompting programmed cell death (1-3). Central to these signaling pathways are the phosphatidylinositol 3-kinase-related kinases (PIKK) 1 Atm (ataxia-telangiectasia mutated) and Atr . Atm along with its downstream transducing partner Chk2 responds to DNA double-strand breaks (2). In contrast, during S-phase, other types of DNA damage independently recruit Atr, claspin, and the heterotrimeric Rad9-Hus1-Rad1 (9-1-1) complex to chromatin (4 -7), where they mediate activation of the protein kinase Chk1 (5,8,9). Activated Chk1 then stabilizes stalled replication forks and impedes S-phase progression by blocking the firing of origins of replication (10 -12).Although much progress has been made in the identification and ordering of checkpoint signaling proteins, it is clear that additional components also participate in the signaling pathways. Possible candidate participants in the pathways are the Cut5/Dpb11/Mus101 orthologs. Cut5 and Dpb11 were identified in Schizosaccharomyces pombe and Saccharomyces cerevisiae, respectively (13,14). Although these proteins are required for DNA replication, they are also essential for activation of the replication checkpoint, indicating that they participate in checkpoint signaling. In higher eukaryotes, orthologs of Cut5 and Dpb11 have also been identified. Drosophila Mus101, human TopBP1, and Xenopus Cut5 (also known as Mus101) are highly related to one another and more distantly related to Cut5/Dpb11 (15-18). In Drosophila, hypomorphic alleles of the Mus101 gene confer sensitivity to genotoxins (19). Likewise, human TopBP1 forms nuclear foci that co-localize with 53BP1, BRCA1, and NBS in response to replication arrest and ionizing radiation (20,21). In addition, human TopBP1 is phosphorylated by PIKKs in response to genotoxic stress and interacts with the checkpoint signaling proteins Rad9 and 53BP1 (20,21). These observations suggest that the putative TopBP1/ Mus101/Cut5 orthologs found in higher eukaryotes also participate cellular responses to DNA damage; however, the role of Cut5 orthologs in checkpoint signaling has not been explored.Besides their role in checkpoint activatio...