A unique amino acid sequence of a k-chain obtained from a patient with adult Fanconi syndrome: a new subset sequence

Amino acid sequences in amyloid proteins of kappa III immunoglobulin light-chain origin

The main amyloid fibril (AL) proteins extracted from the spleen of Patient So 124 with systemic amyloidosis and from a skin nodule of Patient KSA with localized amyloidosis were studied by partial amino acid sequence analysis and proved to be of kappa III immunoglobulin light-chain origin. The sequences were similar to that of Bence Jones protein V and, which has been reported to have a unique kappa III subset sequence. Thus, except for position 9 in protein AL(KSA), the amino acid sequences were identical to position 25 in AL(So 124) and in AL(KSA). The question is being raised whether this kappa III subset might contain amyloidogenic sequences.

Unique amino acid sequences of Bence Jones proteins in the urine of patients with adult Fanconi syndrome

The amino-terminal amino acid sequences of Bence Jones (BJ) proteins isolated from the urine specimens of two patients (JBL and PSM) with adult Fanconi syndrome were determined. Both BJ proteins JBL and PSM are of the VkI subclass. However, protein JBL contains tyrosine at position 14 whereas protein PSM contains glutamine at position 40. Neither tyrosine 14 nor glutamine 40 has previously been reported for immunoglobulin (Ig) L-chains of any species including humans, the mouse, rabbit, rat, guinea pig. pig, dog, chicken, turkey, and shark. In addition, protein JBL contains alanine 22 whereas protein PSM contains arginine 30. Both alanine 22 and arginine 30 have been only rarely found in Ig L-chains.

Unique human glycoprotein, alpha1-microglycoprotein: isolation from the urine of a cancer patient and its characterization

A human glycoprotein was isolated from the urine of a patient with plasma cell leukemia. It appears pure and homogeneous when examined by immunoelectrophoresis, sodium dodecyl sulfate (NaDodSO4)-polyacrylamide gel electrophoresis, gel filtration in 6 M guanidine hydrochloride (Gdn.HCl), and NH2-terminal amino acid sequence analysis. It has a brown color due to a tightly (most likely covalently) bound chromophore group(s) and migrates to the alpha1 region in immunoelectrophoresis. A molecular weight (mol wt) of 27 000 was obtained for the glycoprotein by gel filtration in 6 M Gdn.HCl. Its approximate mol wt determined by Na-DodSO4-polyacrylamide gel electrophoresis is 29 000 on 5% and 7.5% and 10% gels. Amino acid and hexosamine analyses showed that it is a glycoprotein and indicated that it contains four half-cystine residues per molecule. Based on the above observations we designated it "alpha1-microglycoprotein" (alpha1-MGP). Isoelectric focusing of alpha1-MGP showed a significant charge heterogeneity, although only a single NH2-terminal amino acid sequence was obtained for alpha1-MGP, i.e., Gly-Pro-Val-Pro-( )-Pro-Pro-Asx-Asx-Ile-Glx-Val-Glx-Glx-Asx-Phe-Phe-Ile-(Ser or Ala)-Arg. The alpha1-MGP was found in significant concentrations in the urine of many patients with neoplastic diseases.