Red cell enzyme polymorphisms in Bulgaria

Summary 7 human red cell enzyme polymophisms have been typed on a sample of n=138 unrelated adults from Bulgaria, which revealed the following gene frequencies: ADA¹=0.8623. ADA²=0.1376; AK¹=0.9637, AK²=0.0362; 6-PGD^A=0.9891, 6-PGD^C=0.0108; PGM ₁ ¹ =0.8346, PGM ₁ ² =0.1653; P^A=0.1596, P^B=0.7983, P^C=0.0420. In the LDH-system one B-subunit variant was found, whilst no Peptidase A or B variant could be observed. The anthropological significance of these findings is discussed.

---

Zusammenfassung An einer Stichprobe von n=138 nichtverwandten erwachsenen Bulgaren wurden 7 erythrocytäre Enzympolymorphismen untersucht. Dabei ergaben sich die folgenden Frequenzen: ADA¹=0,8623, ADA²=0,1376; AK¹=0,9637, AK²=0,0362; 6-PGD^A=0,9891, 6-PGD^C=0,0108; PGM ₁ ¹ =0,8346, PGM ₁ ² =0,1653; P^A=0,1596, P^B=0,7983, P^C=0,0420. Im LDH-System wurde eine B subunit-Variante gefunden, während keine Peptidase A- oder B-Variante beobachtet werden konnte. Die anthropologische Bedeutung dieser Befunde wird diskutiert.

     

Some notes on the geographical distribution of the human red cell acid phosphatase phenotypes

Summary Basing on the data of 65 populations the geographical variability of the human red cell acid phosphatase phenotypes resp. alleles was studied. We found a marked distribution gradient: The frequency of p^B-alleles increases with the increase of the mean annual temperature of the various biotops, whereas the p^A-allele frequencies show a clear decrease. For this allele we calculated a significant negative correlation between its frequency and the mean annual temperature: r=-0.71; P<0.001. We suppose that the p^B-allele is in some way adaptive under the climatic conditions of tropical biotops. The possible reasons are discussed.

---

Zusammenfassung An Hand der Angaben von 65 Populationen wurde die geographische Variabilität in der Phänotypen- und Allelenverteilung der menschlichen sauren Erythrocytenphosphatasen untersucht. Dabei ergab sich ein deutlicher Verteilungsgradient insofern, als die p^B-Frequenz mit zunehmender mittlerer Jahrestemperatur zunimmt, während die p^A-Frequenz abnimmt. Für dieses Allel konnte eine signifikante negative Korrelation zwischen seiner Frequenz und der mittleren Jahrestemperatur ermittelt werden: r=-0,71; P<0.001. Wir vermuten, daß das p^B-Allel unter den klimatischen Bedingungen tropischer Biotope adaptiver ist. Die möglichen Ursachen hierfür werden diskutiert.

     

Variation of several erythrocyte enzymes and serum proteins of Indonesians from North Sumatra

Summary Indonesians from North Sumatra were surveyed for erythrocyte enzymes and serum protein variants. The gene frequency of 6PGD^C in 264 Batak was 0.051; in small numbers of other racial groups it ranged from 0.016 to 0.060. The gene frequency of PGM ₁ ¹ in 272 Batak was 0.761; in small numbers of other racial groups it ranged from 0.700 to 0.808. PHI type 4-1 was found once in 271 Batak, and PHI 4-1, PHI 3-1, and PHI 6-1 were each found once in 55 Chinese. No variants were found in the MDH and LDH systems. The Hp¹ gene frequency in 271 Batak was 0.284; in small numbers of other racial groups it ranged from 0.216 to 0.292. The Tf D gene frequency in 262 Batak was 0.044, and that of Tf B was 0.002; in small numbers of other racial groups, Tf D gene frequencies ranged from 0.008 to 0.042. Serum albumin Medan and albumin Kuala Lumpur were found at low frequencies.

---

Zusammenfassung Indonesier aus Nord-Sumatra sind auf Erythrocytenenzyme und Serum-Protein-Varianten untersucht worden. Die Genfrequenz von 6PGD^C unter 264 Batak war 0,051; in kleinen Bevölkerungszahlen anderer rassischer Gruppen lag sie zwischen 0,0016 und 0,060. Die Genfrequenz von PGM ₁ ¹ unter 272 Batak betrug 0.761; in kleinen Bevölkerungszahlen anderer rassischer Gruppen lag sie zwischen 0,700 und 0,808. PHI Typ 4-1 fand sich einmal unter 271 Batak, und PHI 4-1, PHI 3-1 und PHI 6-1 wurden je einmal unter 55 Chinesen festgestellt. Im MDH- und LDH-System fanden sich keine Varianten. Die Hp¹-Genfrequenz bei 271 Batak war 0,284; in kleinen Bevölkerungszahlen anderer rassischer Gruppen lag sie zwischen 0,216 und 0,292. Die Häufigkeit des Tf D-Gens bei 262 Batak war 0,044 und die des Tf B-Gens 0,002; in kleinen Bevölkerungszahlen anderer rassischer Gruppen lag die Genfrequenz zwischen 0,008 und 0,042. Das Serumalbumin Medan und-albumin Kuala Lumpur hatten eine geringere Frequenz.

---

---

Supported by the University of California International Center for Medical Research (UC ICMR) through research grant AI 10051 to the Department of International Health, School of Medicine, University of California, San Francisco, from the National Institute of Allergy and Infectious Diseases, National Institutes of Health, U.S. Public Health Service.     

Anthropological studies among Libyans. Erythrocyte genetic factors,serum haptoglobin phenotypes and anthropometry

Anthropological studies were done on 1276 Libyans from the Mediterranean cities of Tripoli and Benghazi, and from Sabha southward in The Sahara. The incidences of hemoglobin (Hb)-S and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency were low in the coastal areas and significantly high in Sabha. Hb-C occurred sporadically in Tripoli and Sabha, and was absent from Benghazi in the east. One case of Hb-J Benghazi was noted. There were no significant differences in the ABO blood group and Rh₀ (D) type distributions in the three localities. G-6-PD gene Gd^A frequency was significantly high in Sabha. The lowest value of 6-phosphogluconate dehydrogenase (6-PGD) gene PGD^A frequency and highest value of the gene PGD^C were in Sabha. Adenylate kinase (AK) gene AK² was only detectable in Tripoli. Acid phosphatase (AP) gene P^a frequency in Sabha was more than twice that in Tripoli and Benghazi, while P^c was distinctly lower in Sabha than in the northern cities. Haptoglobin gene Hp¹ frequency was almost identical in all areas. Anthropometric measurements revealed overall homogeneity of the three samples, closer similarity in the coastal region to adjacent North African populations, and Negroid influence in the Saharan Libyans. Anthropometry substantiated findings from blood markers.     

Identification of self-incompatibility genotypes of almond by allele-specific PCR analysis

In almond, gametophytic self-incompatibility is controlled by a single multiallelic locus (S-locus). In styles, the products of S-alleles are ribonucleases, the S-RNases. Cultivated almond in California have four predominant S-alleles (S ^a, S ^b, S ^c, S ^d). We previously reported the cDNA cloning of three of these alleles, namely S ^b, S ^c and S ^d. In this paper we report the cloning and DNA sequence analysis of the S ^a allele. The S^a-RNase displays approximately 55% similarity at the amino-acid level with other almond S-RNases (S^b, S^c, and S^d) and this similarity was lower than that observed among the S^b, S^c and S^d-RNases. Using the cDNA sequence, a PCR-based identification system using genomic DNA was developed for each of the S-RNase alleles. Five almond cultivars with known self-incompatibility (SI) geno-types were analyzed. Common sequences among four S-alleles were used to create four primers, which, when used as sets, amplify DNA bands of unique size that corresponded to each of the four almond S-alleles; S ^a (602 bp), S ^b (1083 bp), S ^c (221 bp) and S ^d (343 bp). All PCR products obtained from genomic DNA isolated from the five almond cultivars were cloned and their DNA sequence obtained. The nucleotide sequence of these genomic DNA fragments matched the corresponding S-allele cDNA sequence in every case. The amplified products obtained for the S ^a- and S ^b-alleles were both longer than that expected for the coding region, revealing the presence of an intron of 84 bp in the S ^a-allele and 556 bp in the S ^b-allele. Both introns are present within the site of the hypervariable region common in S-RNases from the Rosaceae family and which may be important for S specificity. The exon portions of the genomic DNA sequences were completely consistent with the cDNA sequence of the corresponding S-allele. A useful application of these primers would be to identify the S-genotype of progeny in a breeding program, new varieties in an almond nursery, or new grower selections at the seedling stage. Received: 21 June 1999 / Accepted: 15 November 1999     

Zur Populationsgenetik der sauren Phosphatase der Erythrocyten (EC: 3.1.3.1): Phänotypen- und Allelhäufigkeiten in der ČSSR

Summary Within a population sample of 307 blood donors of Prague the polymorphism of the red cell acid phosphatase has been investigated. Gene frequency estimates are: P^a=0.365, P^b=0.578, P^c=0.057.     

北京山区河岸带植物群落种-面积关系

种-面积关系是群落生态学的基本问题之一,是了解植物群落结构的重要途径。为摸清北京山区河流河岸带植物群落调查最小样方面积,在北京市怀柔区怀九河河岸带沿线,采用基于河岸带立地条件逐步扩大样地面积的方法布设50个80m长样地,调查计算并拟合不同类型河岸带所需的最小样地面积。研究结果表明:北京市怀柔区怀九河河岸带植物种数255种,隶属于70科185属。通过聚类分析将怀九河河岸带分为自然河岸带、近自然河岸带、人工岸坡乔灌草河岸带、人工岸坡观赏性乔灌草河岸带、人工岸坡疏乔灌草干砌石河岸带和人工岸坡浆砌石河岸带6种类型。根据赤池信息量准则AIC可知自然河岸带、近自然河岸带、人工岸坡乔灌草河岸带和人工岸坡疏乔灌草干砌石河岸带优先选取S=c-ae~(-bA),人工岸坡观赏性乔灌草河岸带优先选取S=aA/(1+bA),人工岸坡浆砌石河岸带优先选取S=c/(1+ae~(-bA))。满足相同比例植物种调查,不同类型河岸带所需最小样地面积存在明显差异,当满足河岸带植物调查80%植物种时,人工岸坡浆砌石河岸带(84m~2)和自然河岸带(217m~2)所需样地面积较小,其次是人工岸坡疏乔灌草干砌石河岸带(362m~2),近自然河岸带(450m~2)和人工岸坡乔灌草河岸带(460m~2)所需样地面积相似,而人工岸坡观赏性乔灌草河岸带所需样地面积最大为571m~2。所得出的河岸带植物调查最小样地面积对于河岸带生物多样性保护和指导河岸带生态修复具有重要意义。     

Blutgruppen und Lepra bei moçambiquanischen Völkerschaften

Zusammenfassung Etwa 600 moçambiquanische Eingeborene, vorwiegend Chuabo und Macua wurden auf folgende Blutgruppensysteme bzw. Merkmale untersucht: A B 0, M N S s S^u, C C^wc D E e, K k Kp^aJs^aJs^b, P₁, Fy^aFy^bFy, Jk^aJk^b, Le^a, Di^a, Gc, SEPh, PGM₁, PGM₂ und ADA.Im Durchschnitt gesehen überwiegen die typischen Negermerkmale bei den Moçambiquanern mehr als bei anderen negriden Populationen. Signifikante Unterschiede zwischen verschiedenen Stämmen, insbesondere zwischen Macua, Chuabo, Bitonga und Changane, wurden nicht gefunden. In nahezu allen Systemen unterschieden sich dagegen die leprösen von den nichtleprösen Macua mehr oder weniger deutlich. Im AB0-, MNSS^us-, Rhesus-, Lewis-, Gc- und PGM-System sind die Unterschiede sogar signifikant. Zur Zeit haben wir keine Erklärung für diese Befunde.

---

Blood groups and lepra in populations of moçambique

Summary About 600 natives of Moçambique, preferably Chuabo and Macua were tested for the following blood group systems, resp. markers: A B 0, M N S s S^u, C C^wc D E e, K k Kp^aJs^aJs^b, P₁, Fa^aFy^bFy, Jk^aJk^b, Le^a, Di^a, Gc, SEPh, PGM₁, PGM₂ and ADA.The typical blood group markers for negroes were found to a higher extent than in nearly all the other negroid populations. Significant differences between the single tribes of Moçambique, especially between Macua, Chuabo, Bitonga and Changane were not found. In almost all systems, however, marked differences between leprous and non-leprous Macuas could be detected. These were statistically significant in the AB0-, Rhesus-, Lewis-, Gc- and P.GM-system. At this time no explanation for these findings can be given.

---

---

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.     

Stoffwechsel während der Embryonalund Jugendentwicklung der Lungenschnecken

Zusammenfassung 1. Bei Embryonen vonLymnaea stagnalis wurden Sauerstoffverbrauch, Trockengewicht und Aktivität der-Galaktosidase gemessen, und zwar während der Furchung und Keimblätterbildung (a), bei den Larven (b) und bei älteren Embryonen nach Beginn der Herztätigkeit (c).2. Jede dieser Meßgrößen zeigte während der Entwicklungsabschnitteb undc einen zweiphasigen exponentiellen Anstieg, wobei die Phasenänderung mit dem Einsetzen der Herztätigkeit erfolgte.3. Im Entwicklungsabschnitta stieg nur der Sauerstoffverbrauch exponentiell an. Eine-Galaktosidase konnte zu dieser Zeit noch nicht gefunden werden.4. Die mit dem Einsetzen des Herzschlages erfolgende Änderung der Syntheserate der-Galaktosidase wird als hormonale Steuerung der Genaktivität gedeutet.

---

Metabolism during embryonic and early post-embryonic development

The embryonic development of the snailLymnaea stagnalis may be divided into three main stages: (a) cleavage and gastrulation, (b) larvae and (c) older embryos with beating hearts. During these three stages the following were measured: respiration by means of a Cartesian diver apparatus, embryo dry weight by means of a quartz fiber balance, and activity of-galactosidase (enzymatically with o-Nitrophenyl--D-galactopyranoside as substrate). During stagesb andc a two-phase exponential increase occurs in respiration, in dry weight and in the activity of-galactosidase. Change of phases coincides with the beginning of heart beats. The increase of enzyme activity is explained by assuming a hormonal regulation of the activity of the genes responsible for enzyme synthesis. During stagea only respiration rises exponentially; activity of-galactosidase is not demonstrable.

     

Intensity of nitrification in soil as a function of time and soil moisture

Proceeding from three previously derived expressions for the intensity of nitrification in soil as a function of time (logΣN=K.logt+q), as a function of incubation moisture (logΣN=A.pF _i+B), as a function of initial moisture (logΣN=C.pF _v+D), it was shown that the nitrification intensity as a function of time and of moisture can be expressed by the bilinear function log ΣN=a.pF _i.logT+b.pF _i+c.logt+d; as a function of time and of initial moisture by the bilinear function logΣ=N=a.pF _v.logt+b.pF _v+c.logt+d; as a function of initial and incubation moisture by the bilinear function log ΣN=a.pF _ipF _v+b.pF _i+c.pF _v+d. The intensity of nitrification as a function of time, incubation moisture and initial moisture may be expressed by the multilinear function log ΣN=a.pF _i.pF _v.logt+b.pF _i.pF _v+c.pF _i.logt+d.pF _v.logt+e .pF _i+f.pF _v=g.logt+h. This function is valid for all the incubation moistures lying between pF _i 3.0 and 4.0 and for all initial moistures between 3.5 and 5.9 provided that the incubation temperature remains constant.     

Crystal structures of cyclomaltohexaose (α-cyclodextrin) complexes with p-chlorophenol and p-cresol

Crystal structures of cyclomaltohexaose (α-cyclodextrin) complexes with p-chlorophenol and p-cresol have been determined by single-crystal X-ray diffraction studies. The space group of the α-cyclodextrin–p-chlorophenol complex is P2₁2₁2₁ with unit cell dimensions of a=15.299(3), b=24.795(5), c=13.447(5) Å, and that of the α-cyclodextrin–p-cresol complex is P2₁ with unit cell dimensions of a=7.927(7), b=13.568(7), c=24.54(1) Å, β=90.41(8)°. In spite of the similar structures of guest molecules, both complexes have different inclusion modes and packing structures.     

Daten zur Populationsgenetik der 6-Phosphogluconat-Dehydrogenase

Summary Four Malaysian racial groups were typed for red cell adenylate kinase: 324 Malays, 300 Chinese, 256 Indians, and 483 West Malaysian Aborigines. The AK² gene frequencies found were 0.015, 0.0, 0.086, and 0.013, respectively. All 244 Malays, 170 Chinese, 153 Indians, and 132 West Malaysian Aborigines examined had the common cytoplasmic malate dehydrogenase phenotype.

---

Zusammenfassung Vier Rassengruppen aus Malaysia wurden auf Adenylatkinase-Varianten hin untersucht: 324 Malayen, 300 Chinesen, 256 Inder und 483 Eingeborene von West-Malaysia. Die Genhäufigkeiten des Allels AK² waren: 0,015, 0,0, 0,086 und 0,013. Alle 244 Malayen, 170 Chinesen, 153 Inder und 132 west-malaysischen Eingeborenen, die daraufhin untersucht werden konnten, hatten den häufigen Phänotyp der cytoplasmatischen Malat-Dehydrogenase.

---

---

This work was supported by the University of Maryland and University of California International Centers for Medical Research and Training with research grants AI-10049-12, AI-10051, and HE 10486, all from the National Institutes of Health, U.S. Public Health Service.     

The species–area relationship derived from species-specific incidence functions

The species–area relationship (SAR), describing the increase in species number (S) with increasing area (A), is one of the most robust patterns in ecology with great significance for conservation. The SAR is generally formulated as a power function, S = kA^z, although the semilogarithmic form S = a + b log A has often been used by botanists. Here we unite the two forms by deriving SARs from the incidence functions of the species that make up the community. We show how the decisive scaling parameters z and b relate to the properties of individual species, and highlight why the biological interpretation of SARs has been so enigmatic.     

Photoinduced electron transfer in cytochrome bc1: Dynamics of rotation of the Iron-sulfur protein during bifurcated electron transfer from ubiquinol to cytochrome c1 and cytochrome bL

The electron transfer reactions within wild-type Rhodobacter sphaeroides cytochrome bc₁ (cyt bc₁) were studied using a binuclear ruthenium complex to rapidly photooxidize cyt c₁. When cyt c₁, the iron?sulfur center Fe₂S₂, and cyt b_H were reduced before the reaction, photooxidation of cyt c₁ led to electron transfer from Fe₂S₂ to cyt c₁ with a rate constant of k_a = 80,000 s^?1, followed by bifurcated reduction of both Fe₂S₂ and cyt b_L by QH₂ in the Q_o site with a rate constant of k₂ = 3000 s^?1. The resulting Q then traveled from the Q_o site to the Q_i site and oxidized one equivalent each of cyt b_L and cyt b_H with a rate constant of k₃ = 340 s^?1. The rate constant k_a was decreased in a nonlinear fashion by a factor of 53 as the viscosity was increased to 13.7. A mechanism that is consistent with the effect of viscosity involves rotational diffusion of the iron?sulfur protein from the b state with reduced Fe₂S₂ close to cyt b_L to one or more intermediate states, followed by rotation to the final c₁ state with Fe₂S₂ close to cyt c₁, and rapid electron transfer to cyt c₁.     

Role and strain distribution of genes controlling light chains needed for the expression of an intrastrain cross-reactive idiotype

Several strains of mice were tested for their capacity to provide immunoglobulin L chains required for the expression of the major cross-reactive idiotype (CRI_A) associated with p-azophenylarsonate-specific antibodies of strain A mice. To facilitate testing, mice were bred that were homozygous for Igh-C ^e and Lyt-2 ^a , 3 ^a , i. e., they possessed genes controlling H chains but not L chains required for expression of the CRI_A. Such male mice were mated to females of various strains and their offspring were tested; expression of CRI_A indicated the presence in the female parent of genes controlling the appropriate L chains. All females bearing the Lyt-2 ^a , 3 ^b or Lyt-2 ^b , 3 ^b genotype yielded offspring, most of which were CRI _A ⁺ , whereas all the offspring of females that were Lyt-2 ^a , 3 ^a were CRI _A ^– . The female parents included mice of several strains that are congenic for Lyt-2 ^a , 3 ^b , Lyt-2 ^b , 3 ^b or Lyt-2 ^a , 3 ^b , thus demonstrating very close linkage between the Lyt loci and the expression of CRI_A. In addition, doubly congenic strains of mice with the heavy chain allotype of the CRI _A ⁺ AL/N strain and the Lyt-2 ^a , 3 ^a genotype on a BALB/c background failed to express CRI_A. The data provide further evidence for the similarity of repertoires of L chains in Lyt-3 ^b mice of various strains. When genes were present controlling A/J H chains and L chains of C57BL/6 or BALB/c origin, the quantitative expression of CRI_A was only slightly lower than that observed in A/J mice. Mice possessing genes controlling the H or L chains required for CRI_A expression, but not both, did not express CRI_A but synthesized Ar-specific antibodies which contained low but significant concentrations of the idiotype-associated chain.     

Zur Populationsgenetik der sauren Phosphatase der Erythrocyten (E C 3.1.3.2): Phänotypen-und Allelhäufigkeiten in Südwestdeutschland

Summary Within an population sample of 300 individuals of Southwestern Germany the red cell acid phosphatase polymorphism is investigated. Gene frequency estimates are: P^a=0.31, P^b=0.643, P^c=0.047.

---

---

Direktor: Prof. Dr. med. Dr. H. Baitsch

---

Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.     

Effect of mutations affecting coat color on the blood lymphocyte structure in the american mink (<Emphasis Type="Italic">Mustela vison</Emphasis> Schreber, 1777)

American minks with different genotypes containing the Aleutian coat color allele in the homozygous state, including the single recessive Aleutian (a/a); double recessive sapphire (a/a p/p) and lavender (m/m a/a); triple recessive violet (m/m a/a p/p); and dominant-recessive cross sapphire (S/+ a/a p/p), sapphire leopard (S ^K /+ a/a p/p), and shadow sapphire (S ^H /+ a/a p/p) minks, as well as American minks without the Aleutian allele, including the standard (+/+); single recessive silver-blue (p/p) and hedlund-white (h/h); double recessive pearl (k/k p/p), Finnish topaz (t ^S /t ^S b/b); incompletely dominant royal silver (S ^R /+), standard leopard (S ^K /+), and black crystal (C _R /+); and dominant-recessive snowy topaz (C _R /+ t ^S /t ^S b/b) and Kujtezhyspotted (S ^K /+ b/b) minks have been studied. Homozygosity for the a allele has been found to disturb the subcellular structure of leukocyte, namely the formation of abnormally large granules.     

Malate dehydrogenase isozymes in the longnose dace,Rhinichthys cataractae

The interspecies homology of dace supernatant (A₂, AB, B₂) and mitochondrial (C₂) malate dehydrogenase isozymes has been established through cell fractionation and tissue distribution studies. Isolated supernatant malate dehydrogenase (s-MDH) isozymes show significant differences in Michaelis constants for oxaloacetate and in pH optima. Shifts in s-MDH isozyme pH optima with temperature may result in immediate compensation for increase in ectotherm body pH with decrease in temperature, but duplicate s-MDH isozymes are probably maintained through selection for tissue specific regulation of metabolism.This research was supported in part by NSF Grant SM176-83974 and a grant from the Blakeslee Fund.     

A genetically controlled lactate dehydrogenase variant at the B locus in mink

Erythrocytes of 119 mink, and tissue extracts of three mink, were examined for electrophoretic patterns of lactate dehydrogenase (LDH). A variant was detected at the B locus. There are two alleles, LDH-B ^a and LDH-B ^b; three phenotypes, LDH-Ba, LDH-Bab, and LDH-Bb; and three genotypes, LDH-B ^a/LDH-B^a, LDH-B^a/LDH-B^b, and LDH-B ^b/LDH-B^b. The inheritance as observed in 24 families agrees with an autosomal, codominant, two-allele system at the LDH B locus.Supported by National Research Council Grant A-4442 and the Ontario Department of Agriculture and Food.     

Thiosulfate-linked ATP-dependent NAD+ reduction in Rhodopseudomonas palustris

Summary A cytochrome containing fraction virtually devoid of the photosynthetic apparatus (bacteriochlorophyll and/or chromatophores) was isolated from Rps. palustris grown photolithotrophically with S₂O₃ ⁼as the exogenous electron donor. This fraction contained predominantly cytochromes of c, a and o type and exhibited thiosulfate: cytochrome c oxidoreductase and ferrocytochrome c:O₂ oxidoreductase activities. Under anaerobic conditions the enzyme preparation catalyzed an ATP-dependent NAD⁺ reduction by S₂O₃ ⁼in the dark involving a reversal of electron transfer from cytochrome c and yielding a molar stoichiometry of approximately 2:1 for the ferrocytochrome c oxidized and NAD⁺ reduced. In this process approximately 4 to 7 molar equivalents of ATP were utilized/equivalent of NAD⁺ reduced. The optimal reaction occurred at pH 8.0 and in the presence of 55 M added mammalian cyt. c, 1.7 mM Mg⁺⁺, 1.7 mM ATP and 7.0 mM S₂O₃ ⁼. The S₂O₃ ⁼-linked ATP-driven reduction of NAD⁺ as well as the coupled oxidation of cyt. c were inhibited completely by 5 m CCCP or 10 M DNP and the reaction was also markedly sensitive to other uncouplers of the energy transfer reactions. The pathway of electron transfer from S₂O₃ ⁼ to NAD⁺ appears to involve cyt. c, b, and flavoprotein systems as evidenced by the complete inhibition of the process by low concentrations of antimycin A, NOQNO, rotenone and amytal.Non-standard abbreviations BAL British Anti-Lewisite (2,3-Dimercaptopropanol) - CCCP Carbonyl-cyanide-m-chlorophenylhydrazone - DBP 2,6-Dibromophenol - DNP 2,4-Dinitrophenol - EDTA Ethylenediamine tetraacetic acid - GSH reduced glutathione - NOQNO 2-n-Nonyl-4-hydroxyquinoline-N-oxide - PCP Pentachlorophenol - PABA p-aminobenzoic acid. Post doctorate fellow of the Deutsche Forschungsgemeinschaft