TABLE 2.

Analytical characterization of three lots of G-hLAL

Protein Property	LSBC040929L	LSBC040811L	LSBC040623L
Puritya	99.00%	99.60%	98.40%
Identity: Average molecular mass (Da)b	50,383	50,402	50,772
Identity: Principal molecular mass (Da)b	49,032, 49,635, 50,700, 52,167	49,303, 50,660, 51,244	49,003, 50,808, 52,506
Identity: Matched tryptic peptidesb	10	10	10
Identity: N-terminal sequencec	Passed	Passed	Passed
Protein concentration (mg/ml)	1.33	0.69	1.64
Protein aggregation (monomer %:multimer %)d	97.8:2.2	85:15	97:3
Specific activity (U/mg protein)	364.5	281	360
pH	7.0	7.3	7.3
Bioburden	Passedg	Passed	Passed
Endotoxin (EU/mg)e	<1	<1	<1
Residual TMVf	Passedh	Passed	Passed

EU, endotoxin unit; TMV, tobacco mosaic virus.

^aPurity was determined by SDS-PAGE and densitometry scanning analysis.

^bThe identity of the protein was determined by molecular mass of the full-length protein and the molecular matching of 10 tryptic peptides using matrix-assisted laser desorption-ionization time-of-flight mass spectrometry.

^cThe identity of the protein was determined by N-terminal amino acid sequencing of the first 10 residues (sequenced by Protein Structure Core Facility, University of Michigan).

^dProtein aggregation (monomer vs. multimer) was determined by size exclusion chromotography.

^eEndotoxin was determined by Limulus Amebocyte Lysate assay as described (28).

^fInfectivity of G-hLAL was determined by local lesion bioassay as described (28).

^gThe criteria for “passed” is zero colony-forming units per mg protein.

^hThe criteria for “passed” is zero infectious TMV particles per mg protein.