Fungal metabolic profile dataset was not influenced by long-term in vitro preservation of strains

Comparative ecophysiology is highly valuable approach to reveal adaptive traits linked with specific ecological niches. Although long-term in vitro preserved fungal isolates are often used for analyses, only sparse data is available about the effect of such handling on fungal physiology. The purpose of our data is to show the effect of long-term in vitro preservation of fungal strains on their metabolic profiles. This data is related to research paper “Adaptive traits of bark and ambrosia beetle-associated fungi” (Veselská et al., 2019). Biolog MicroPlates™ for Filamentous fungi were used to compare metabolic profiles between freshly isolated and long-term in vitro preserved strains of two Geosmithia species. Additionally, carbon utilization profiles of 35 Geosmithia species were assessed, including plant pathogen G. morbida and three ambrosia species. Data also shows differences in carbon utilization profiles among diverse ecology types presented in the genus Geosmithia.


Data
Biolog MicroPlate™ for Filamentous fungi was used to assess carbon sources utilization profiles of Geosmithia fungi living in symbiosis with bark beetles [1]. Their ecology spans from facultative to obligatory ambrosia symbiosis and from saprotrophic to pathogenic nourishment of severe phytopathogen G. morbida (Table 1). The aims were to test whether metabolic profiles of Geosmithia species are modified by their ecology and whether long-term preservation of strains has effect on their metabolic profiles. The distinct metabolic profiles belonging to particular ecology types are pictured in Fig. 1 and Table S1. The similarity in metabolic profiles of freshly isolated and long-term preserved strains of Geosmithia sp. 5 and G. langdonii is shown in Fig. 1 and Table S1. Raw data containing growth value of individual strains on each carbon source is presented in Table S1. Raw data is helpful for further identification of adaptive traits of important ambrosia and pathogenic species.

Fungal strains
The metabolic profiles of 60 strains belonging to 35 Geosmithia species (Table 1) were analyzed. These strains are deposited in the Culture Collection of Fungi (CCF) or at Institute of Microbiology of the Czech Academy of Sciences for several years. Then, two species, G. sp. 5 and G. langdonii, were chosen and the effect of long-term in vitro preservation (0e10 years) on fungal carbon assimilation profiles was observed. Fresh strains of these species were isolated from active beetle galleries in 2009 and identified as it is described in Pepori et al. [2]. These strains were analyzed within a 2 months on Biolog Micro-Plates™ for Filamentous fungi. Altogether, three "old" and six "new" strains of G. sp. 5 and four "old" and four "new" strains of G. langdonii were compared. The species classification follows Kola rík et al. [3].

Value of the Data
Comparative ecophysiology is valuable tool for tracing of species adaptive traits and identification of potential virulence factors in plant, animal and human pathogenic fungi. Usually, long-term in vitro preserved isolates are used for physiological analysis, but little is known about the effect of such handling on fungal physiology. Presented data investigate the reliability of using the long-term preserved fungal cultures for physiological analysis. Data disproves negative effect of long-term preservation on fungal metabolic profile, which enables researchers to use such strains for physiological studies. Data shows metabolic profiles of carbon utilization for most of Geosmithia species which includes also ambrosia fungi and severe phytopathogen G. morbida.
Raw data provides growth values on each carbon source. This is helpful for further identification of adaptive traits of these important species. Ecology: PF e association with phloem feeding beetles, G e generalist, SF e specialists to Fagus, SP e specialist to Pinaceae, HWS e hardwood specialists, P e pathogen, AF eambrosia fungi, AAF e auxiliary ambrosia fungi.

Biolog MicroPlate™ for Filamentous fungi
Biolog MicroPlate™ for Filamentous fungi contains 95 different dried carbon sources and one negative control. Fungal conidia from grown cultures were transferred into the inoculating fluid (0.25% Phytagel, 0.03% Tween 40) by rolling a swab across sporulating areas to get the final transmittance of 75 ± 2%. The inoculated plates (200 ml per well) were then incubated in the dark at 25 C and absorbance at 750 nm was used to measure mycelial growth at 24, 48, 72, 96 and 168 h. An absorbance reading taken 96 h after the inoculation was included in the analysis, because sporulation occurred in some strains after that time. Two technical replicates per strain were prepared.

Statistical analysis
The absorbance of the negative control was subtracted from all substrates within one plate and negative values were assigned a value of zero [4]. Biolog™ data were visualized on PCA (Principal Component Analysis) in PAST program [5]. The statistical significance of the type of ecology was evaluated by one-way NPMANOVA with Bonferroni-corrected p values using Bray-Curtis distance and 9999 permutations.

Acknowledgments
The project was founded by Czech Science Foundation project GACR 16-15293Y. langdonii. Based on one-way NPMANOVA, facultative generalists were significantly (p < 0.005) different from long-term co-evolved specialists and phytopathogen.