Involvement of rcsB in Klebsiella K2 capsule synthesis in Escherichia coli K-12

Escherichia coli K-12 harboring a part of the structural genes for the Klebsiella K2 capsular polysaccharide (cpsK*) expresses a large amount of K2 capsular polysaccharide as a thick capsule in the presence of plasmids carrying rmpA and rcsB. We have previously shown that expression of the Klebsiella K2 capsule in E. coli HB101 harboring cpsK* depends on the presence of rmpA, a regulatory gene from a large plasmid of Klebsiella pneumoniae Chedid (O1:K2). E. coli K-12 JM109, however, produces only a small amount of K2 capsular polysaccharide, even in the presence of plasmids carrying rmpA as well as the cpsK* structural genes. Introduction of the rcsB gene, a positive regulator of colanic acid capsule synthesis in E. coli K-12 which was cloned from HB101 on a plasmid, into JM109 cells carrying cpsK* and rmpA, results in the expression of a thick K2 capsule. By Northern (RNA) hybridization analysis, rcsB has been found to enhance transcription of a long strand of mRNA (longer than 14 kb) from cpsK*. These E. coli transformants which produce a thick K2 capsule also express colanic acid production at high levels. Therefore, rcsB can act as a positive regulator of Klebsiella K2 capsule production and two capsular polysaccharides can be expressed in E. coli simultaneously. With a somewhat different strain background, we have found that both of the colanic acid regulators, rcsA and rcsB, contribute to the basal level of Klebsiella K2 capsule expression but that the presence of multicopy rcsB in either an rcsB or an rcsA mutant of E. coli is sufficient to increase the expression of K2 capsular polysaccharide. These results suggest further parallels between the regulation of colanic acid synthesis in E. coli and the regulation of Klebsiella K2 capsule synthesis.

Inhibitory effects of N- and C-terminal truncated Escherichia coli recA gene products on functions of the wild-type recA gene

The effects of the expression of Escherichia coli truncated RecA protein on the host recA functions were examined. The recA gene on a multicopy plasmid was manipulated to express the truncated RecA protein from its carboxyl (C) and amino (N) terminal ends where a maximum of four extra amino acid residues was added. The regulatory part of the recA gene was substituted by the lacUV5 promoter in the plasmid to facilitate the artificial control of recA expression. Enzyme-linked immunosorbent assay and Western blot analyses revealed great differences in accumulation of the truncated RecA proteins in the cell, depending on the location of the site of truncation. The expression of truncated proteins lacking 62, 77, 93 or 149 amino acid residues from the C-terminal end caused the host recA+ wild-type cell to become sensitive to ultraviolet irradiation and interfered with chromosomal recombination but did not interfere with the induction of lambda prophage. The expression of truncated RecA protein with 25 amino acid residues deleted from the C-terminal end caused the host cell to induce SOS functions constitutively. Truncated RecA proteins with 15 or 28 amino acid residues missing from the N-terminal end severely interfered with all of the host recA functions examined here. The effect of the loss of 41 amino acid residues from the N-terminal end of RecA was significant but less than the effect of proteins lacking 15 or 28 amino acid residues from the N-terminal end. A protein lacking 59 amino acid residues from the N-terminal end showed little interference with any measured recA functions, suggesting that the deletion of the region from around residues 41 to 59, which is rich in hydrophobic side-chains, influenced the ability of the truncated protein to interfere with the functions of wild-type RecA protein. We also constructed a mutant gene with an internal deletion whose product was missing a region from residues 184 to 204. That mutant RecA protein was stably accumulated in the cell. This protein had little effect on the function of host wild-type recA gene product. The possible function of the regions at the N and C termini are discussed.

C-terminal truncated Escherichia coli RecA protein RecA5327 has enhanced binding affinities to single- and double-stranded DNAs

RecA5327 is a truncated RecA protein that is lacking 25 amino acid residues from the C-terminal end. The expression of RecA5327 protein in the cell resulted in the constitutive induction of SOS functions without damage to the DNA. Purified RecA5327 protein effectively promoted the LexA repressor cleavage reaction and ATP hydrolysis at a lower concentration of single-stranded DNA than that required for wild-type RecA protein. A DNA binding study showed that RecA5327 has about ten times higher affinity for single-stranded DNA than does the wild-type RecA protein. Moreover RecA5327 protein binds stably to double-stranded (ds) DNA in conditions where the wild-type RecA protein could not bind. The binding of RecA5327 protein to dsDNA was associated with the unwinding of dsDNA, suggesting that RecA5327 binds to dsDNA in the same manner as does the wild-type protein. The fact that RecA5327 does not bind stoichiometrically but forms short filaments on dsDNA suggests that it nucleates to dsDNA much more frequently than does the wild-type protein. The role of the 25 C-terminal residues, in the regulation of RecA binding to DNA, is discussed.

Platelet-activating factor detected in bronchoalveolar lavage fluids from an asthmatic patient

It recently has been recognized that platelet-activating factor (PAF) may be a mediator of asthma exacerbation. We had the opportunity to analyze bronchoalveolar lavage fluids from an asthmatic infant, which were characterized by neutrophil infiltration. The patient's lungs were washed on three occasions with saline during asthmatic attacks. PAF was found in each case on the basis of its ability to cause the immediate aggregation of washed rabbit platelets. The PAF detected was equivalent to 1-1.4 pmol of 1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine, three quarters of which were recovered in cell-associated form. By contrast, we did not detect PAF in bronchoalveolar exudates from patients with laryngeal stenosis or with respiratory distress syndrome. LysoPAF, the direct precursor as well as initial metabolite of PAF, was also analyzed after being converted to PAF by acetylation. There was a wide variation in the amount of lysoPAF present in individual patients, suggesting that lysoPAF levels cannot be taken as an indicator for the presence of PAF.

Effect of dietary alpha-linolenate on platelet-activating factor production in rat peritoneal polymorphonuclear leukocytes

The effects of dietary alpha-linolenate (18:3, n-3) and linoleate (18:2, n-6) on platelet-activating factor (PAF) production were examined. Rats were fed an alpha-linolenic acid-rich (perilla oil) diet or a linoleic acid-rich (safflower oil) diet for 6 wk, and polymorphonuclear leukocytes (PMN) were elicited by peritoneal injection of casein. The overall phospholipid content and composition as well as the subclass distribution of choline and ethanolamine glycerophospholipids in PMN were not altered by these diets. However, with the perilla oil diet their content of a putative precursor of PAF, 1-alkyl-2-arachidonoyl-sn-glycero-3-phosphocholine was approximately 50% of that with safflower oil diet. On exposure to various concentrations of FMLP, PAF formation by PMN in the perilla oil group was less than 50% of that by PMN in the safflower oil group. A larger difference in PAF productions by PMN in the two dietary groups was observed on their stimulation with calcium ionophore A23187. These results demonstrate that PAF production is modulated in some as yet unknown way by changing the alpha-linolenate/linoleate balance of the diet.

Effect of dietary alpha-linolenate on platelet-activating factor production in rat peritoneal polymorphonuclear leukocytes

The effects of dietary alpha-linolenate (18:3, n-3) and linoleate (18:2, n-6) on platelet-activating factor (PAF) production were examined. Rats were fed an alpha-linolenic acid-rich (perilla oil) diet or a linoleic acid-rich (safflower oil) diet for 6 wk, and polymorphonuclear leukocytes (PMN) were elicited by peritoneal injection of casein. The overall phospholipid content and composition as well as the subclass distribution of choline and ethanolamine glycerophospholipids in PMN were not altered by these diets. However, with the perilla oil diet their content of a putative precursor of PAF, 1-alkyl-2-arachidonoyl-sn-glycero-3-phosphocholine was approximately 50% of that with safflower oil diet. On exposure to various concentrations of FMLP, PAF formation by PMN in the perilla oil group was less than 50% of that by PMN in the safflower oil group. A larger difference in PAF productions by PMN in the two dietary groups was observed on their stimulation with calcium ionophore A23187. These results demonstrate that PAF production is modulated in some as yet unknown way by changing the alpha-linolenate/linoleate balance of the diet.

An autopsy case of I-cell disease. Ultrastructural and biochemical analyses

An autopsy case of I-cell disease in a 4-year-old Japanese girl is presented. In this report, the authors analyze the relationship between morphologic (including electron microscopic) and biochemical findings. Lymph node, spleen, and kidney, which were stained with Hale's colloidal iron method, contained large amounts of hexosamine. These substances had accumulated in lymphocytes of B-cell lineage.

Construction of a novel suicide vector: selection for Escherichia coli HB101 recombinants carrying the DNA insert

We constructed a new type of cloning vector, pERISH2, that transforms Escherichia coli HB101 only when a foreign DNA fragment is ligated into the cloning site of the plasmid vector. Plasmid pERISH2 carries the rcsB gene which is derived from the chromosome of E. coli HB101 and is involved in the regulation of colanic acid production. When E. coli HB101 is transformed by this vector carrying the intact rcsB gene, the gene product RcsB blocks bacterial growth. However, if the rcsB gene is inactivated by the insertion of a foreign DNA fragment, this recombinant plasmid no longer inhibits the growth of E. coli HB101. Although E. coli HB101 is not stably transformed by pERISH2, E. coli K-12 strains such as JM109 and C600 can harbor this vector. Therefore, pERISH2 can be amplified in JM109 and be prepared from this strain in a large quantity using conventional methods. A chromosomal gene library of Klebsiella pneumoniae is constructed easily and efficiently by the utilization of this new cloning vector.

Head to head dimer model; an alternative model for the strand exchange reaction by RecA protein of Escherichia coli

The RecA protein of E coli promotes a strand exchange reaction in vitro which appears to be similar to homologous genetic recombination in vivo. A model for the mechanism of strand transfer reaction by RecA protein has been proposed by Howard-Flanders et al based on the assumption that the RecA monomer has two distinctive DNA binding sites both of which can bind to ssDNA as well as dsDNA. Here, I propose an alternative model based on the assumption that RecA monomer has a single domain for binding to a polynucleotide chain with a unique polarity. In addition, the model is based on a few mechanical assumptions that, in the presence of ATP, two RecA molecules form a head to head dimer as the basic binding unit to DNA, and that the binding of RecA protein to a polynucleotide chain induces a structural change of RecA protein that causes a higher state of affinity for another RecA molecule that is expressed as cooperativy. The model explains many of the biochemical capabilities of RecA protein including the polar polymerization of RecA protein on single stranded DNA and polar strand transfer of DNA by the protein as well as the formation of a joint DNA molecule in a paranemic configuration. The model also presents the energetics in the strand transfer reaction.

Synthesis and antiviral activities of carbocyclic oxetanocin analogues

9-Cyclobutyladenine (4a), cis- and trans-9-[3- (hydroxymethyl)cyclobutyl]adenine (4b) and 9-[3,3-bis(hydroxymethyl)cyclobutyl]adenine(4d) were prepared from the corresponding cyclobutylamine derivatives (1a, 1b and 1d). Guanine congeners (9a, cis- and trans-9b and 9d) and carbocyclic oxetanocin G (1',2'-trans-9f) were also prepared. Carbocyclic oxetanocin A(1',2'-trans-4f), the preparation of which we have already published, and G were found to be active against herpes simplex virus (type 1 and 2) in vitro, while cis-4b and cis-9b showed an in vitro antiretroviral activity against human immunodeficiency virus (type 1).

[Ovarian metastasis in patients with cervical cancer]

The study included a total of 634 patients with cervical cancer; 311 were in stage I b and 323 were in stage II. All patients received radical hysterectomy at the Department of Obstetrics and Gynecology, Kinki University, between May 1975 and December 1986. One out of 311 patients in stage I b (0.3%) and eight out of 323 patients in stage II (2.5%) had ovarian metastases confirmed histologically. Nine patients who had ovarian metastases were investigated about stages, histological types of the cervical cancer (WHO and CPL classification), incidence of metastases in pelvic lymph nodes, corpus infiltration, parametrial infiltration, and peritoneal cytology. Results obtained were as follows: 1. As to histological types, patients with adenocarcinoma and/or PL type in CPL classification had high incidence of ovarian metastases. 2. Patients with corpus infiltration had high incidence of ovarian metastases. 3. Metastases to both ovary and pelvic lymph nodes tended to occur on the same side, but ovarian metastases and parametrial infiltration did not necessarily occur on the same side. We suggest removal of ovaries, even before menopause, in patients with cervical cancer who have cervical adenocarcinoma, or corpus infiltration, or are suspicious for metastases in more than two pelvic lymph nodes.

Replication of ColE2 and ColE3 plasmids: in vitro replication dependent on plasmid-coded proteins

We developed an in vitro replication system for ColE2 and ColE3 plasmids using cell extracts prepared from bacteria with or without these plasmids. DNA synthesis depended on host DNA polymerase I and was sensitive to rifampicin and chloramphenicol. Preincubation of the extracts with plasmid DNA, however, allowed replication of template DNA added subsequently in a plasmid-specific manner in the presence of rifampicin and chloramphenicol. The plasmid-specified trans-acting factor(s) was detected in cell extracts from bacteria carrying a recombinant plasmid with the region of ColE2 or ColE3 encoding the Rep protein. The plasmid-specified factor(s) consisted at least in part of protein, probably the Rep protein. In vitro replication started within a region of ColE2 or ColE3 containing the smallest cis-acting segment essential for in vivo replication and proceeded in a fixed direction.

Structure and expression of the Plasmodium falciparum SERA gene

Plasmodium falciparum, strain FCR3, genomic DNA that encodes the SERA gene of P. falciparum was isolated and sequenced. The SERA gene coding region was interrupted by 3 introns, the largest number observed, so far, in any Plasmodium gene. Two SERA gene alleles, allele I and allele II, were identified in the FCR3 strain, while only allele I was found in the Honduras-1 strain. Allele I mRNA was abundant in vivo during the late trophozoite and schizont stages. Allele II mRNA was either not expressed, or it was labile.

Structural and functional organization of ColE2 and ColE3 replicons

The complete nucleotide sequences of the 1.5 kb regions of ColE2 and ColE3 plasmids containing the segments sufficient for autonomous replication have been determined. They are quite homologous (greater than 90%), indicating that these two plasmids share common mechanisms of initiation of replication and its regulation. An open reading frame with a coding capacity for a protein of about 300 amino acids is present in both ColE2 and ColE3 and it actually specifies the Rep (for replication) protein, which is the plasmid specific trans-acting factor required for autonomous replication. The amino acid sequences of the Rep proteins of ColE2 and ColE3 are quite homologous (greater than 90%). The cis-acting sites (origins) where replication initiates in the presence of the trans-acting factors consist of 32 bp for ColE2 and 33bp for ColE3. They are the smallest of all the prokaryotic replication origins so far reported. They are nonhomologous only at two positions, one of which, a deletion of a single nucleotide in ColE2 (or an insertion in ColE3), determines the plasmid specificity in interaction of the origins with the Rep proteins. Both plasmids carry a region with an identical nucleotide sequence and the one in ColE2, the IncA region, has been shown to express incompatibility against both ColE2 and ColE3. These results indicate that these plasmids share a common IncA determinant. A possibility that a small anti-sense RNA is involved in copy number control and incompatibility (IncA function) was suggested.

Significance of para-aortic node irradiation in the treatment of cervical cancer

In 1980, we introduced para-aortic node irradiation as a part of our treatment of cervical cancer. Eighty-six patients with cervical cancer were selected for such treatment, based on histologic or radiologic criteria for lymph node involvement. We delivered 45 Gy to the para-aortic nodes in 5 weeks. Comparison studies on the prognosis and on the incidence of side effects with and without para-aortic node irradiation were carried out on a total of 783 patients who had invasive cervical cancer and were treated from 1975 to 1984. For patients in stages Ib and II who met, or before 1980 would have met, our criteria there was no significant difference in survival for those in stage Ib, but in stage II the para-aortic node irradiation group did significantly better (P less than 0.01). For the entire series of patients, for all stages from Ib to IV, the prognosis for the group treated after the introduction of para-aortic node irradiation was superior, with a statistically significant difference from the prognosis for patients treated before the introduction of this mode (Ib, P less than 0.05; II, P less than 0.01; III, P less than 0.01; IV, P less than 0.05). None of the patients had severe complications after para-aortic node irradiation. We conclude that, by irradiating the para-aortic nodes, we can improve the prognosis of cervical cancer patients who may have para-aortic node involvement, a situation which formerly was considered hopeless.

Replication of ColE2 and ColE3 plasmids: two ColE2 incompatibility functions

We have identified and localized two incompatibility determinants (IncA and IncB) within a 1.3 kb segment of ColE2 sufficient for autonomous replication. The IncA determinant is localized in a region shorter than 250 bp and expresses incompatibility against both ColE2 and ColE3. The region which determines sensitivity to the IncA determinant seems to overlap with the region specifying the IncA determinant. The expression of the trans-acting factor(s) specifically required for replication of ColE2 interferes with expression of the IncA determinant against ColE2 but not against ColE3. The IncA determinant might be at least partly responsible for the copy number control of the plasmid. The IncB determinant is localized in a 50 bp region (origin) which is sufficient for initiation of replication in the presence of the trans-acting factor(s). The IncB determinant is specific for ColE2 and seems to be due to titration of the trans-acting essential replication factor(s) by binding.

Amino acid sequence of the serine-repeat antigen (SERA) of Plasmodium falciparum determined from cloned cDNA

We report the isolation of cDNA clones for a Plasmodium falciparum gene that encodes the complete amino acid sequence of a previously identified exported blood stage antigen. The Mr of this antigen protein had been determined by sodium dodecylsulphate-polyacrylamide gel electrophoresis analysis, by different workers, to be 113,000, 126,000, and 140,000. We show, by cDNA nucleotide sequence analysis, that this antigen gene encodes a 989 amino acid protein (111 kDa) that contains a potential signal peptide, but not a membrane anchor domain. In the FCR3 strain the serine content of the protein was 11%, of which 57% of the serine residues were localized within a 201 amino acid sequence that included 35 consecutive serine residues. The protein also contained three possible N-linked glycosylation sites and numerous possible O-linked glycosylation sites. The mRNA was abundant during late trophozoite-schizont parasite stages. We propose to identity this antigen, which had been called p126, by the acronym SERA, serine-repeat antigen, based on its complete structure. The usefulness of the cloned cDNA as a source of a possible malaria vaccine is considered in view of the previously demonstrated ability of the antigen to induce parasite-inhibitory antibodies and a protective immune response in Saimiri monkeys.

Characterization of antigen-expressing Plasmodium falciparum cDNA clones that are reactive with parasite inhibitory antibodies

A Plasmodium falciparum (FCR3 strain) lambda gt11 cDNA expression library was constructed from trophozoite and schizont poly(A) RNA and was screened immunologically with a pooled human immune serum from Nigeria to form a gene bank of 288 positive clones. The gene bank was subsequently screened with parasite inhibitory mouse monoclonal antibodies (mMAb) and with individual human Liberian sera. Two mMAb, 43E5 and 5H10, strongly reacted with 8 and 3 cDNA clones, respectively. Several of those clones also weakly cross-reacted with the other mMAb. Two of those weakly cross-reactive clones, cDNA#366 and cDNA#22, were shown to be located in different chromosomal regions of the parasite by Southern hybridization and so appeared to represent two different parasite genes. The genomic organization of both cDNA#366 and cDNA#22 sequences were identical in the FCR3 and the Honduras-1 strain. The nucleotide sequence of cDNA#366 and the amino acid sequence it coded for were homologous to a partial DNA and amino acid sequence previously reported for a P. falciparum (Camp strain) exoantigen designated p126. The mRNA for cDNA#366 appeared to represent an abundant message in blood stage trophozoites and schizonts.

Replication of ColE2 and ColE3 plasmids: the regions sufficient for autonomous replication

We have localized the regions sufficient for autonomous replication on the genomes of the colicin E2 (ColE2) and colicin E3 (ColE3) plasmids and analyzed the replication functions carried by these regions. A 1.3 kb segment of each plasmid is sufficient for autonomous replication. Plasmids carrying this segment retain the replication properties of the original plasmid. The 1.3 kb segment consists of three functional portions. Firstly, a 0.9 kb region which specifies at least one trans-acting factor required for replication of each plasmid. Secondly, a 0.4 kb region located adjacent to one end of the 0.9 kb region, which is required for expression of the trans-acting factor(s) and probably contains the promoter. The region across the border of these two portions of ColE2 is involved in copy number control of the plasmid. The third portion is a 50 bp region adjacent to the other end of the 0.9 kb region, which contains a cis-acting site (origin) where replication initiates in the presence of the trans-acting factor(s). The action of the trans-acting factor(s) on the origin is plasmid specific. The 50 bp regions functioning as the origins of replication of ColE2 and ColE3 are the smallest among those in prokaryotic replicons so far identified and analyzed.

Molecular cloning and sequence analysis of the Plasmodium falciparum dihydrofolate reductase-thymidylate synthase gene

Genomic DNA clones that coded for the bifunctional dihydrofolate reductase (DHFR) and thymidylate synthase (TS) (DHFR-TS) activities from a pyrimethamine-sensitive strain of Plasmodium falciparum were isolated and sequenced. The deduced DHFR-TS protein contained 608 amino acids (71,682 Da). The coding region for DHFR-TS contained no intervening sequences and had a high A + T content (75%). The DHFR domain, in the amino-terminal portion of the protein, was joined by a 94-amino acid junction sequence to the TS domain in the carboxyl-terminal portion of the protein. The TS domain was more conserved than the DHFR domain and both P. falciparum domains were more homologous to eukaryotic than to prokaryotic forms of the enzymes. Predicted secondary structures of the DHFR and TS domains were nearly identical to the structures identified in other DHFR and TS enzymes.

Pyrimethamine resistant Plasmodium falciparum: overproduction of dihydrofolate reductase by a gene duplication

The accumulation of [3H]pyrimethamine by pyrimethamine-resistant (Pyrr) mutants of the Plasmodium falciparum strain FCR3 was examined by measuring the accumulation of drug in infected red blood cells. [3H]Pyrimethamine was stage specifically accumulated in trophozoites and schizont infected red blood cells. The mutant parasites accumulated drug as efficiently as FCR3. Pyrimethamine was associated with a high molecular weight protein that eluted from a Sephadex G200 column exactly as [3H]fluorodeoxyuridinemonophosphate (FdUMP) labeled parasite dihydrofolate reductase-thymidylate synthetase (DHFR-TS) enzyme. These results suggested that the pyrimethamine resistance was not associated with decreased drug permeability of the membrane. DHFR-TS-[3H]FdUMP enzyme complex of all the Pyrr mutants and FCR3 had a monomer of 70 kDa as measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. One highly resistant mutant, FCR3-D7, exhibited a 5-10 fold higher uptake of pyrimethamine and a proportionately higher amount of DHFR-TS protein than FCR3 but only a normal level of DHFR activity. The genomic DNA of FCR3-D7 was shown to contain at least twice as much DHFR-TS specific DNA than either FCR3-D8, another Pyrr mutant, or FCR3. Preliminary results suggested some of the DHFR-TS genetic material in FCR3-D7 is associated with a gene duplication.

[Fundamental and clinical studies on cefuzonam in the field of obstetrics and gynecology]

Fundamental and clinical studies on cefuzonam (CZON, L-105), a new cephem antibiotic, were carried out. The results obtained are summarized as follows: 1. Upon drip infusion of 1 g CZON, a good transfer of the drug into female genital organ was observed. The transfer of CZON into exudates of the pelvic dead space was also good. 2. Clinical efficacy of CZON was good in 1 case we tested. No side effect was observed.

Production of recombinant human pancreatic secretory trypsin inhibitor by Escherichia coli

A synthetic gene for human pancreatic secretory trypsin inhibitor (PSTI) was fused to the coding sequence for the amino-terminal 135 amino acid residues of human interferon-gamma (IFN-gamma) by interposing a methionine codon sequence, and the resulting hybrid gene was efficiently expressed in Escherichia coli cells. Recombinant human PSTI (rHu-PSTI) was separated from the IFN-gamma/PSTI fused protein by cleavage at the methionine residue with cyanogen bromide. Finally, rHu-PSTI was purified by affinity chromatography on a bovine trypsin-CH-Sepharose 4B column. The amino acid composition, partial amino-terminal sequence, disulfide formation, human trypsin inhibitory activity, and immunoreactivity against rabbit anti-human PSTI serum of rHu-PSTI corresponded to those of the natural form.

Congenital absence of lacrimal puncta and of all major salivary glands: case report and literature review

A 7-year-old girl had dry mouth and recurrent infections of the lacrimal fistulae with decreased lacrimal secretion. All four puncta were absent, and a Schirmer test showed decreased lacrimal secretion. Salivary gland imaging with sodium pertechnetate 99mTcO4 showed absence of all major salivary glands. Lower lip biopsy disclosed normal structure of the salivary gland. No evidence of abnormal inheritance patterns could be demonstrated.

[Fundamental and clinical studies of imipenem/cilastatin sodium in the field of obstetrics and gynecology]

Fundamental and clinical studies of imipenem/cilastatin sodium (MK-0787/MK-0791), a new carbapenem antibiotic, were carried out. The results obtained were summarized below. At a dose of 500 mg/500 mg, the penetration of MK-0787/MK-0791 into internal genital organs was good. The penetration of MK-0787/MK-0791 into pelvic dead space exudate was also good. Clinical results obtained were good in 4 patients and poor in 1, with an efficacy rate of 80%. No side effects were observed, but 1 patient showed slight elevations of GOT, GPT, Al-P and LDH. From these results, MK-0787/MK-0791 appeared to be a useful drug for the treatment of various infections in the field of obstetrics and gynecology.

[Fundamental and clinical studies on aztreonam in the field of obstetrics and gynecology]

Fundamental and clinical studies were performed on aztreonam (AZT), a new antibiotic with single beta-lactam ring, with the following results. Following intravenous drip infusion of 1 g, transfer of AZT to the internal genital organs was found to be good. Transfer of AZT to exudate of pelvic dead space was also good. AZT was given to 6 cases, who had gynecological or obstetrical infectious disease. AZT was effective in the 5 cases out of 6, although it showed high MIC against bacteria isolated from the effective cases. The above results demonstrated that AZT was a safe and effective drug.

[Basic and clinical studies on cefminox in the field of obstetrics and gynecology]

Basic and clinical studies were carried out on cefminox (CMNX, MT-141), a new cephem antibiotic. Results obtained were as follows. Following each 1 g of intravenous drip infusion and intravenous injection, transfer of CMNX to the internal genital organs was good. Transfer of CMNX into exudate of the pelvic dead space was also good and showed high concentration. CMNX was given to 2 cases. Clinical efficacy was good in 1 case, and could not be evaluated in 1 case. No side effects were observed in both cases. The above results show that CMNX is an effective agent.

[Fundamental and clinical studies on cefpimizole in the field of obstetrics and gynecology]

The findings from fundamental and clinical studies on cefpimizole (AC-1370) in the treatment of infections in obstetrics and gynecology are reported. We investigated the transfer of AC-1370 into female genital tissues of 6 patients and the transfer of the drug into the pelvic dead space exudate in 9 patients by means of determining its concentrations in the tissues 90 to 210 minutes after the end of intravenous drip infusion of the drug over 1 hour. The mean concentration was 13.06 micrograms/g for the oviduct, 16.50 micrograms/g for the ovary, 16.50 micrograms/g for the endometrium, 14.92 micrograms/g for the myometrium, 16.58 micrograms/g for the uterine cervix, 17.75 micrograms/g for the portio vaginalis, 10.46 micrograms/ml for the uterine arterial serum and 9.91 micrograms/ml for the antecubital venous serum. The drug proved to be well transferred into the pelvic dead space exudate; it reached a peak of mean 2 hours after the end of the intravenous drip infusion of the drug over 1 hour, then decreased steadily, and was found to be a mean of 16.7 micrograms/ml even 8 hours after the end of the intravenous drip infusion. Four patients with infections in obstetrics and gynecology were then treated with AC-1370. Three out of the 4 patients responded to the treatment, while the response of another patient was unknown. None of the 4 patients showed any side effects of the drug or any abnormalities in laboratory findings.

[Fundamental and clinical studies of ceftriaxone in the field of obstetrics and gynecology]

Fundamental and clinical studies on ceftriaxone (Ro 13-9904, CTRX), a new cephem antibiotic, were carried out with the following results. Following each 1.0 g of drip infusion, transfer of CTRX to female genital organs was found to be excellent. Transfer of CTRX to exudate of the pelvic dead space was also excellent. And high concentration of CTRX was kept for long time after administration. CTRX was given to 7 cases. It was effective for 5 cases and ineffective for 2 cases. The above results demonstrated that CTRX is a safe and effective drug.

[Clinical studies on sulbactam/cefoperazone in the field of obstetrics and gynecology]

Sulbactam (SBT), a new beta-lactamase inhibitor, in combination with cefoperazone (CPZ) was studied for the clinical efficacy in the field of obstetrics and gynecology. SBT/CPZ was given to 5 cases with the following infections; 2 of pyometra, 2 of endometritis and 1 of abscess of adnexa. Clinical efficacy was good in 3 cases and poor in 2 cases. Bacteriologically, only 1 strain of P. vulgaris was beta-lactamase producer but was persisted after treatment. Neither side effects nor abnormal laboratory findings was observed.

Molecular cloning of cDNA for rat glycine methyltransferase

Using a highly purified preparation of glycine methyltransferase mRNA, double-stranded cDNA was synthesized and inserted into the PstI site of pBR322. The resulting recombinant DNA was used to transform E. coli X 1776 by conventional methods. Among tetracycline-resistant transformants, a number of colonies were found to contain cDNA sequence for glycine methyltransferase as examined by hybrid-selected translation. A restriction endonuclease cleavage map was constructed covering about 720 base pairs. With the cDNA as the probe, the content of the glycine methyltransferase mRNA was quantitated in various rat tissues and was found to be proportional to the specific enzyme activity.

Cysteinyl residues of Escherichia coli recA protein

The Escherichia coli recA protein has three cysteinyl residues at positions 90, 116, and 129. All of them are reactive with 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB). In the presence of ATP or ADP, only one cysteinyl residue reacts with DTNB. The residue was also reactive with N-[7-(dimethylamino)-4-methylcoumarinyl]maleimide (DACM) in the presence of ATP. The results on an analysis of the DACM-modified protein cleaved at the nonmodified cysteinyl residues after cyanation with 2-nitro-5-(thiocyano)benzoic acid show that two cysteinyl residues protected in the presence of ATP or ADP are identified as Cys-90 and Cys-129. When the ionic strength is higher than 1, one cysteinyl residue does not react with DTNB. This residue is Cys-90 or Cys-129, because one of the two cysteinyl residues, which are not modified with DACM in the presence of ATP, does not react with DTNB at high ionic strength. The binding of single-stranded DNA to the recA protein does not change the reactivity of the cysteinyl residues with DTNB.

Functional domains of Escherichia coli recA protein deduced from the mutational sites in the gene

The sites of recA mutations of Escherichia coli, recA441 (tif-1), recA1, recA430 (lexB30) and recA44, were determined by analyses of the nucleotide sequences. All mutations are single point missense mutations within the coding region of the recA gene. In the recA441, recA1, recA430 and recA44 proteins, the 38th, 160th, 204th, and 246th amino acids, respectively, from the amino terminal ends are altered. Based on the properties of these mutant proteins and modified forms of recA protein, the locations of various regions of the recA protein that are involved in binding with ATP, binding with single-stranded DNA, hydrolysis of ATP, interaction between the recA protein molecules and interaction with the lambda cI or lexA repressors are mapped on the primary structure of the protein.

[Fundamental and clinical studies on ceftazidime in the field of obstetrics and gynecology]

Fundamental and clinical studies were carried out on ceftazidime ( CAZ ), a new cephalosporin antibiotic, with the following results. Following each 1.0 g of drip infusion and bolus intravenous injection, transfer of CAZ to the internal genital organs was found to be good. Transfer of CAZ into exudate of the pelvic dead space was also good. CAZ was given to 6 cases. Clinical efficacy was good in 5 cases and poor in 1 case. No side effects were observed in any case. The above results demonstrated that CAZ is a safe and effective drug.

Regulation of SOS functions: purification of E. coli LexA protein and determination of its specific site cleaved by the RecA protein

The LexA protein of Escherichia coli was purified to more than 96% purity from cells harboring a recombinant plasmid carrying the lexA gene with the lacZ promoter sequence. The amino acid composition of the LexA protein and its amino-terminal sequence were analyzed. The results are in agreement with the prediction from the nucleotide sequence of the lexA gene. The LexA protein is cleaved into two polypeptides by E. coli RecA protein in the presence of ATP and single-stranded DNA. The site of the specific cleavage was determined by analyzing amino acid sequences of the cleaved products at the amino and carboxyl termini. The cleavage of the LexA protein by the RecA protein was found to occur at a single site between Ala84 and Gly85.

Nucleotide sequence of the lexA gene of E. coli

Using a cloned fragment containing the lexA gene of E. coli, the entire nucleotide sequence of the lexA gene has been determined. The probable coding region of the lexA gene contains 606 nucleotide residues and encodes a single protein of 202 amino acids. The initiation site of in vitro transcription of the lexA messenger RNA has been determined by analysis of the 5' nucleotide sequence. Comparison of the DNA sequence of the promoter region of the lexA gene with that of the recA gene reveals the presence of sequences that are common to both. There is some similarity between the amino acid sequences of the lexA and the lambda repressor proteins.

Organization of the recA gene of Escherichia coli

The restriction map of a BamHI DNA fragment that contains the recA gene of Escherichia coli has been established and a large portion of the fragment's nucleotide sequence has been determined. The coding region of the recA gene contains 1059 nucleotide residues and encodes a single protein of 353 amino acid residues. The amino acid sequence of the first five residues of the NH2 terminus of the recA protein agrees with the sequence predicted from the DNA sequence except for the absence of formylmethionine in the purified protein. Immediately after the coding sequence, there is a G+C-rich sequence with dyad symmetry followed by an A+T-rich sequence. These could signal termination of transcription. The site of initiation for synthesis in vitro of the recA messenger RNA has been determined by analysis of the 5' nucleotide sequence of [gamma-32P]ATP-labeled transcripts. The promoter region shos a high degree of symmetry and contains sequences commonly found in recognition and binding sites for RNA polymerase.