Haemophilus seminalis sp. nov., isolated from human semen

Abstract

Two Haemophilus-like isolates with similar biochemical characteristics, designated strains SZY H1 T and SZY H2, were isolated from human semen specimens. Cells were Gram-negative, non-motile, non-acid-fast, pleomorphic rods or coccobacilli. The major fatty acids (>10 %) were C 16 : 0 , C 14 : 0 , iso-C 16 : 0 and/or C 14 : 0 3-OH and C 16 : 1 ω6c and/or C 16 : 1 ω7c. The polar lipids were determined to be phosphatidylethanolamine, phosphatidylglycerol, an unidentified phospholipid, an unidentified aminophospholipid, two unidentified polar lipids and four unidentified aminolipids. The major polyamine was found to be cadaverine. The near-full-length (1462 nt) 16S rRNA gene sequences analysis showed the two isolates were nearly identical (>99.8 %), and closely matched Haemophilus haemolyticus ATCC 33390 T with 98.9-99.1 % sequence similarities. Phylogenetic analysis based on 16S rRNA gene sequences and concatenation of 30 protein markers also revealed that the isolates clustered together with H. haemolyticus ATCC 33390 T , and formed a distinct lineage well separated from the other members of the genus Haemophilus. Further, the average nucleotide identity values between the two isolates and their related species were below the established cutoff values for species delineation (95 %). Based on these findings, the two isolates are considered to represent a new species of the genus Haemophilus, for which name Haemophilus seminalis sp. nov. is proposed. The type strain is SZY H1 T (=NBRC 113782 T =CGMCC 1.17137 T).

Phylogeography and host specificity of Pasteurellaceae pathogenic to sea-farmed fish in the north-east Atlantic

“…uteri within ANI similarities of ~81–83% ( Figure 3 ), which is significantly above the mean genus demarcation boundary of 73.98% estimated by Barco et al ( 2020 ) across 858 bacterial and archaeal genera. Moreover, the ANI-based NJ tree in Figure 4 shows that these three taxa together form a distinct monophyletic branch similar to those formed by other sensu stricto representatives (Christensen and Bisgaard, 2018 ; Kirchner et al, 2019 ; Zheng et al, 2020 ) of various Pasteurellaceae genera, including Pasteurella . Taken together, these results present a compelling case for the reallocation of Pasteurella skyensis and “ Pasteurella atlantica ” to the genus Phocoenobacter , although further work will be necessary to clarify and validly publish their precise taxonomic position.…”

“…Type strain genome assemblies from 12 selected sensu stricto (Christensen and Bisgaard, 2018 ; Kirchner et al, 2019 ; Zheng et al, 2020 ) species belonging to the Pasteurellaceae genera Pasteurella ( P. dagmatis and P. multocida subspp. multocida, gallicida , and septica ), Haemophilus ( H. aegyptius, H. haemolyticus, H. influenza , and H. seminalis ), and Actinobacillus ( A. capsulatus, A. pleuropneumoniae, A. suis , and A. vicugnae ) were downloaded from the NCBI GenBank repository (see Supplementary Table S2 for genome accession nos.).…”

Comparative Genomic Analysis Reveals Genetic Diversity and Pathogenic Potential of Haemophilus seminalis and Emended Description of Haemophilus seminalis

“…The genus Haemophilus is a heterogenous group and has been reported as a normal inhabitant of the upper respiratory tract of humans, the oral cavity, and mucous membranes ( 1 – 11 ). The new entry among the Haemophilus isolates is the description of two isolates with the name H. seminalis to indicate its isolation from the clinical semen samples of two patients who were suspected to be infected with Neisseria gonorrhoeae ( 9 ). This study further adds to the repertoires of Haemophilus isolates.…”

“…The isolates previously described as “ H . intermedius ” or hi Hh should be included with the species description, as given by Zheng et al ( 9 ), with the following amendments.…”

“…intermedius ”, and “ H . quentini ”, was first isolated from clinical semen samples as a suspected case of Neisseria gonorrhoeae infection by using chocolate agar PolyViteX ( 9 ). So far, there are no other reports of H. seminalis identification from other human sources.…”