PubMed Health⌕ Search

Biomedical subjects

B Brimhall

Publications and source records attributed to B Brimhall.

At least 37 records · Page 2Linked to original sources

Preliminary survey of carnivore hemoglobin compositions. Conclusions.

The amino acid differences among 12 beta chains and 10 alpha chains of carnivore hemoglobins are given. These hemoglobins conform to the substitution rate found for hemoglobins in general. A table compares the differences among known alpha-chain sequences when deduced from tryptic petide compositions and when taken from actual sequences. Among the carnivore hemoglobins studies, tryptic peptide compositions are about 14 % low in giving the number of sequence differences.

Amino Acid Sequence↗

Hemoglobin SC, SS/GPhiladelphia and SOArab diseases diagnostic importance of an integrative analysis of clinical, hematologic and electrophoretic findings.

Hemoglobin studies are presented on two children in whom electrophoretic analysis of hemolysates at alkaline pH initially suggested the diagnosis of hemoglobin SC disease. In both patients the course of the disease was unusually severe, blood smears contained irreversibly sickled cells, and crystal formation did not occur when red cells were incubated in 3 per cent sodium chloride solution. Each of these findings is inconsistent with the interpretation of the electrophoretic patterns. Family studies demonstrated that one of the patients had sickle cell anemia and was also a carrier of an alpha chain variant; citrate agar electrophoresis at pH 6.2 of the second child's hemolysate revealed that the "C-like" hemoglobin was not hemoglobin C. Tryptic peptide analyses of the nonhemoglobin S fractions showed that the first child has SS/GPhiladelphia disease and that the second child has SOArab disease. These observations emphasize the importance of integrating the clinical and hematologic data with the results of electrophoretic procedures in order to define precisely the hemoglobin abnormality in patients with sickling disorders.

Anemia, Sickle Cell↗

alpha-chain sequence of newt haemoglobin (Taricha granulosa).

The amino acid sequence of the alpha-chain of the major haemoglobin of a newt, T. granulosa, has been determined. The chain is 142 residues long and has an extra methionine at its N-terminus when compared with human alpha-chain. Most of the tryptic peptides were sequenced by a combination of the subtractive Edman method and by deduction from the compositions of overlapping fragments produced by various enzymic treatments. The sequence of two 'core' regions was obtained by automatic sequencing of large peptides produced by trypsin cleavage at arginine residues only after blockage of lysine residues by citraconylation; by cleavage between aspartic acid and proline residues with 70% formic acid, and by cyanogen bromide cleavage at methionine residues. The sequence of T. granulosa alpha-chain is compared with those of representative species from the other classes of vertebrates. The differences in alpha-chain between the classes of vertebrates are compared with the differences in this protein between an equal number of orders of mammals. This comparison allows us to conclude that the major functional and conformational features of alpha-chain have been conserved since the divergence of the classes of jawed vertebrates.

Amino Acid Sequence↗

Hemoglobin Vancouver [alpha2beta2(73)(E17) Asp replaced by Tyr]: its structure and function.

Hemoglobin Vancouver is a new abnormal hemoglobin with an amino acid substitution of the normal aspartyl residue 73 of the beta chain by a tyrosyl residue. It was discovered in a man of Chinese descent in association with beta thalassemia. It was subsequently detected in a sister in association with normal Hb A. The oxygen affinity of the abnormal hemoglobin is decreased but its subunit interaction is normal. The Bohr effect may be slightly increased. This is the fourth abnormal hemoglobin to be found with a substitution at beta73. The others are Hb C-Harlem (alpha2beta2 6Glu replaced by Val and 73 Asp replaced by Asn), Hb Korle-Bu (alpha2beta2 73Asp replaced by Asn), and Hb Mobile (alpha2beta2 73Asp replaced by Val). Although Hb Mobile was found in the present studies to have a decreased affinity for oxygen, Hbs C-Harlem and Korle-Bu have been reported to be normal. These observations of functional differences for variants of beta73 added to earlier observations of the role of the normal beta73 residue to the aggregation of sickle deoxyhemoglobin indicate that this position of the molecule may be important in intra as well as intermolecular interactions.

Amino Acid Sequence↗

Multiple structural genes for the alpha chain of canine (Canis familiaris) hemoglobin.

There are two forms of the alpha chain of canine hemoglobin differing only at residue 130. One form (taualpha) contains threonine at this position, the other (Aalpha) contains alanine. Studies of two Labrador dog families strongly support the existance of multiple alpha-chain structural genes as the basis of the alpha-chain heterogeneity. There must be at least one gene locus for Talpha and one for Aalpha; the exact number of loci has not been determined. Two other dog breeds, the Basenji and the Beagle, also have both Talpha and Aalpha chains.

Alanine↗

Characterization of hemoglobin Burke [beta 107 (G9) Gly replaced by Arg].

Hb Burke [beta 107 (G9) Gly replaced by Arg] was discovered in a young woman with hemolytic anemia. A substitution in this position has not been previously reported either in the human beta-chain or in any of the animal beta-chains so far sequenced. The abnormal hemoglobin shows heat instability and a lowered oxygen affinity. The substitution of a large charged arginine residue for the small glycine residue in the G helix next to a heme contact (Leu-106) may be responsible for these effects. Hb Burke is compared with five other hemoglobins having Gly-Arg substitutions in other parts of the molecule.

Adult↗

A hypothesis for the increased oxygen affinity in haemoglobin Malmö.

Haemoglobin Malmöbeta97His leads to Gln, a high oxygen affinity haemoglobin which causes secondary erythrocytosis, is transmitted in an autosomal dominant manner. A hypothesis accounting for the high oxygen affinity, hyperbolic oxyhaemoglobin dissociation curve, and the relatively normal Bohr effect is presented. The purified abnormal haemoglobin from the present family provided biochemical and functional data for this hypothesis based on the allosteric model proposed by Perutz. Experimental results support the formation of a chemical bond between the -SH proton of the beta93 cysteine and the amide of oxygen of the substituted beta97 glutamine as an explanation for the high oxygen affinity of haemoglobin Malmö.

Hemoglobinopathies↗

Abnormal hemoglobins in a quarter million people.

Hemolysates of erythrocytes from more than a quarter million people in Alabama were electrophoresed on cellulose acetate, pH 8.4, and those samples exhibiting an abnormality were also electrophoresed in citrate agar, pH 6.0. The globin chains of mutants other than Hb S and C were electrophoresed in urea-mercaptoethanol buffers at both pH 8.9 and pH 6.0, and 60 of them were also analyzed structurally. Of about 6000 samples from whites, only three contained abnormal hemoglobins--Hb D Los Angeles, Hb J Baltimore, and one unidentified. Of 249,000 samples from blacks, about 29,000 contained electrophoretically detectable abnormalities, most of them associated with Hb S or C, present in a frequency of about 9% and 3%, respectively. About 1000 samples resolved into patterns of potential clinical significance. Twenty other mutant hemoglobins were detected, in various genetic combinations in 164 kindreds; four of these-Hb Alabama, Montgomery, Titusville, and Mobile--were previously unknown. The methods used are rapid, economical, and well suited for large scale surveys. They provide highly specific characterizations of many mutant hemoglobins, and no discrepancies were found between the presumptive identifications based on these characterizations and the definitive identifications obtained from structural analyses.

Alabama↗

Haemoglobin F Victoria Jubilee (alpha 2 A gamma 2 80 Asp-Try).

A new A gamma chain haemoglobin variant, haemoglobin F Victoria Jubilee, with an electrophoretic mobility slightly anodal to haemoglobin F Port Royal, was found in a Jamaican infant. The amino acid residue substitution of 80 Aspartic Acid leads to Tyrosine was associated with alanine in position 136. Haemoglobin F Victoria Jubilee constituted about 7.0 percent of the total haemoglobin F.

Adult↗

Two new hemoglobins. Hemoglobin Alabama (beta39(C5)Gln leads to Lys) and hemoglobin Montgomery (alpha 48(CD 6) Leu leads to Arg).

The amino acid substitutions in two new hemoglobins found by electrophoretic screening during a survey in Alabama have been determined by column chromatography and amino acid analyses of their tryptic peptides. They are hemoglobin Alabama (beta 39(C 5)Gln leads to Lys) and hemoglobin Montgomery (alpha 48(CD 6) Leu leads to Arg). No harmful symptoms have been attributed to the presence of either hemoglobin.

Adult↗

Hb Mobile [alpha2beta2 73(E17)Asp replaced by Val]: a new variant.

A new hemoglobin variant found in a mother and her child was characterized by column chromatography of the tryptic hydrolysate of the aminoethylated, glycinamidated beta-chain, followed by chymotryptic digestion of the abnormal beta T-9 peptide and amino acid analyses. It was shown to be alpha2beta2 73(E17)Asp replaced by Val and named by Hb Mobile.

Adult↗

Polycythemia produced by hemoglobin Osler (beta-145 (HC2) Tyr yields Asp).

Polycythemia in a black woman was associated with hemoglobin Osler. In this hemoglobin the tyrosine at the penultimate position of the beta chain is replaced by aspartic acid. As a result oxygen affinity of the hemoglobin is very high, heme-heme interaction is absent, and the influence of hydrogen ion and 2,3 diphosphoglycerate on oxygen affinity is attenuated.

Adult↗