title: Characterization and expression of HLysG2, a basic goose-type lysozyme from the human eye and testis.
abstract: Lysozyme plays an important role in human innate immunity by causing bacterial cell lysis. We describe for the first time, the actual performance of human lysozyme g-like 2 (HLysG2), a mammalian g-type lysozyme. RT-PCR revealed that the HLysG2 gene was transcribed in eye and testis tissues. A spot was detected from human tears using 2D gel electrophoresis and was identified as HLysG2 using MALDI-TOF/TOF MS and a MASCOT search with a matching score of 140 and 27% sequence coverage of the whole amino acid sequence. To gain insight into the in vitro antimicrobial activities of HLysG2, the mature peptide-coding region was cloned into Pichia pastoris for heterogeneous expression. Recombinant HLysG2, had an optimal at pH 6.0 and 30 °C, reached the peak activity of 1.2 × 10(4)U/mg at the sodium ion concentration of 75 mM and showed a higher salt tolerance than human c-type lysozyme (HLysC). Recombinant HlysG2 inhibited Gram-positive bacterial growth and did not inhibit Gram-negative bacterial and Candida albicans growth. Results indicated that HLysG2 is a potent antibacterial protein that may play a role in the innate immunity of the human eye.
authors.affiliation: State Key Laboratory of Genetic Engineering, Fudan University, Shanghai 200433, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Huang
authors.forename: Wen-shu
authors.initials: WS
authors.lastname: Li
authors.forename: Jun
authors.initials: J
authors.lastname: Xie
authors.forename: Xian-mei
authors.initials: XM
authors.lastname: Yang
authors.forename: De-ke
authors.initials: DK
authors.lastname: Jiang
authors.forename: Songmin
authors.initials: S
authors.lastname: Jiang
authors.forename: Long
authors.initials: L
authors.lastname: Yu
mesh_terms: D000595:Amino Acid Sequence; D000890:Anti-Infective Agents / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects / Q000254:growth & development; D004591:Electrophoresis, Polyacrylamide Gel; D005123:Eye / Q000201:enzymology*; D020869:Gene Expression Profiling; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D006801:Humans; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D008297:Male; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D009113:Muramidase / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013666:Tears / Q000187:drug effects / Q000201:enzymology; D013696:Temperature; D013737:Testis / Q000201:enzymology*
chemical_list: D000890:Anti-Infective Agents; D011994:Recombinant Proteins; D009113:Muramidase