Proteomic dataset comparing strains of Leptospira borgpetersenii serovar Hardjo cultured at different temperatures

Leptospirosis is a global zoonotic bacterial disease which is a threat for humans and most mammals. Bacterin vaccines for leptospirosis are available however they are severely limited in cross protection between serogroups. Leptospira typically colonize the kidneys of reservoir hosts where they are subsequently shed in the urine and persist in the environment and can thus be indirectly or directly transmitted to incidental hosts. Leptospira borgpetersenii serovar Hardjo is the primary cause of leptospirosis in cattle which can result in abortion, unhealthy calves, and rebreed problems. This dataset comprises proteomic profiles of four strains of L. borgpetersenii serovar Hardjo propagated at the routinely utilized culture temperature of 29 °C, and a newly achieved culture temperature of 37 °C, which more closely emulates the temperature of an infected host. The strains analyzed include JB197 (established strain that causes Hardjo atypical acute disease in the hamster model of leptospirosis), HB203 (established strain, causes typical chronic disease in hamsters), as well as TC129 and TC273 (recently isolated strains from the central United States). Differential expression profiles were detected not only between strains but also within strains between culture temperatures. Mass spectrometry data are available via ProteomeXchange with identifier PXD032831.


a b s t r a c t
Leptospirosis is a global zoonotic bacterial disease which is a threat for humans and most mammals. Bacterin vaccines for leptospirosis are available however they are severely limited in cross protection between serogroups. Leptospira typically colonize the kidneys of reservoir hosts where they are subsequently shed in the urine and persist in the environment and can thus be indirectly or directly transmitted to incidental hosts. Leptospira borgpetersenii serovar Hardjo is the primary cause of leptospirosis in cattle which can result in abortion, unhealthy calves, and rebreed problems. This dataset comprises proteomic profiles of four strains of L. borgpetersenii serovar Hardjo propagated at the routinely utilized culture temperature of 29 °C, and a newly achieved culture temperature of 37 °C, which more closely emulates the temperature of an infected host. The strains analyzed include JB197 (established strain that causes Hardjo atypical acute disease in the hamster model of leptospirosis), HB203 (established strain, causes typical chronic disease in hamsters), as well as TC129 and TC273 (recently isolated strains from the central United States). Differential expression profiles were detected not only between strains but also within strains between cul-

Value of the Data
• These data illustrate distinct proteomic profiles associated with highly similar genomic strains of L. borgpetersenii serovar Hardjo and demonstrate the role of temperature, as encountered during host infection, in regulating protein expression. • These data illustrate strain to strain variation in protein expression and provide reference comparisons for additional strains and serovars of L. borgpetersenii , as well as additional species of Leptospira . • Understanding strain to strain variation is critical to bacterin vaccine design and efficacy.
• The proteomic expression information provided here serves as a reference for the behavior of L. borgpetersenii serovar Hardjo strains in response to change in temperatures encountered during host infection.

Data Description
Data describes whole cell proteomics of four strains of L. borgpetersenii serovar Hardjo (JB197, HB203, TC129, TC273) cultured at 29 °C and 37 °C. Raw mass spectrometry data was analyzed by MaxQuant and Perseus for differential protein expression of interest. The 50 most highly expressed proteins across all strains and conditions are shown in Table 1 . Full data and specific Table 1 The fifty most highly expressed proteins across all strains and conditions based on abundance scores generated by MaxQuant and Perseus analysis. Proteins identified by UniProt ID and Fasta annotation. Shown are average abundance score by strain and condition combination over four biological replicates.

Trypsin Digestion
Samples were digested according to manufacturer's directions with Trypsin/Lys-C Mix (Promega Corporation, Madison, WI) as previous reported [3] . After digestion, samples were run through a desalting Pierce C18 spin column (Thermo Fisher Scientific, West Palm Beach, FL) according to manufacturer's instructions. After drying by vacuum (Speedvac), samples were resuspended in 95% H 2 O 5% acetonitrile and 0.1% formic acid.

Mass Spectrometry
Mass spectrometry and peptide chromatography were completed as done previously [4] . The Thermo Dionex UltiMate 30 0 0 RSLCnano system (Thermo Fisher Scientific, FL, USA) instrument was utilized for peptide chromatography. Chromatography was accomplished with a gradient of buffer A (95% H2O: 5% acetonitrile and 0.1% formic acid) and buffer B (5% H2O: 95% acetonitrile and 0.1% formic acid) over an Acclaim PepMap 100 C18 column. The LC was connected to a Nanospray Ion Source (Thermo Fisher Scientific, FL, USA) on a LTQ OrbiTrap Velos Pro (Thermo Fisher Scientific, FL, USA) mass spectrophotometer. The mass spectrometer used these settings: MSMS scanning resolution was 15,0 0 0, the 40 0 to 20 0 0 m/z MS resolution was 30,0 0 0, the repeated mass duration exclusion was 1 min, and CID activation was utilized (normalized with a collision energy of 35). A signal minimum of 50 0 0 was required for the MS Top 10. The L . borgpetersenii serovar Hardjo-Bovis database was downloaded from UniProt (August 2020). The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE [5] partner repository with the dataset identifier PXD032831.

Analysis of Proteomic Data
Raw mass spectrometry data went through initial processing by MaxQuant (Version 1.6.7.0) [6] followed by subsequent Perseus analysis [7] as reported previously [3] . MaxQuant fixed modifications consisted of Carbamidomethyl (C) and variable modifications included acetyl (Protein N-term), deamidation (NQ), oxidation (M), and Phosphorylation (STY). In Perseus, data was log2 transformed, single peptide identified proteins were removed, and differential expression contrasts were calculated and reported in completion in Supplementary Table 1. For summary of the fifty most highly expressed proteins across strain and temperature shown in Table 1 , all abundance scores generated in MaxQuant and Perseus were summed and sorted to identify the fifty most abundant proteins. Table one shows the average abundance score per strain and temperature condition among four biological replicates.

Statistical Analysis
Perseus software was used to analyze proteomics data [7] . Differential expression utilized a P-value < 0.01 for significant differences.

Declaration of Competing Interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Data Availability
Proteome comparison of Leptospira borgpetersenii serovar Hardjo strains cultured at different temperatures (Original data) (PRIDE Proteomics Identification Database).